There's flippa.com and the likes, you could start your research there.
For an app the quality/maintainable/upgradeability would certainly come into play. As well as things such as growth trends, competition, etc.
But if you can show a market dominant app with a happy user base and steady income that is relatively easy to maintain you can generally expect 3 to 7 times your annualized seller discretionary earnings (A.k.a., your profits minus the cost of replacing your time with a paid programmer and putting back any write-offs that you put on the business).
Secondly, 13,000 line of code is tiny compared to many (most?) commercial apps. I wouldn't consider anything under a million lines of source code as a 'big' code base.
Define "complex" - is that 38 elements, 130, 510, or 927? Do modals count?
Define a "line" - JS can be minified, Elm is terse. Do you count libraries?
The problem is you're speaking in such vague, ambiguous generalities that you're also falling into the trap of focusing on having "impressive" lengths rather than the nuances of making things in the real world.
As a reference point of reference, CryEngine2 checks in at 1M lines of code and undoubtedly had a large team of developers working on it full time.
It does take a long time for 1 person to write 100k of non-auto generated, tested, documented code. Especially multi platform. But it is definitely doable. I've done it.
I wrote Pascal programs as a kid that were 10KLoC.
LoC is a terrible metric because it's not the size that matters, but how it's used. Smaller that does more is more secure, less buggy, and more nimble inherently.
Edit: A small amount of code can be unique, powerful, and took a great deal of art and skill to arrive at.
In computer science, no. No because first off how much of the code did you copy paste from one part to the other? But it is a measure of effort. For instance, secretaries do in fact get paid basically for their character count. And for myself, since I am measuring myself and am not trying to cheat myself, line count is actually not a terrible measure of how much went into a project. But instead of lines, count characters. That actually corresponds to the difficulty of typing, and to the size of the codebase. Yeah it's terrible but come on. Most bosses are impressed by line count. One YC company asked how many lines of code I had written over the course of my entire life...what were they called...hey it's a discrete number. Tells you something. And most code in my opinion, outside Common Lisp, Scheme, Clojure as another poster talked about, code size measures something. Like you're doing it right now, you looked at my comment, said "oh look a wall of text", meaning it doesn't even matter what I pull out of my ass at this point because you won't even read this far. Lines of code.
So I approached the whole thing as a computer scientist, like hey if we have a problem we soon will solve it by designing an algorithm or data structure[1] that speeds things up dramatically. Shockingly even. I think I've gotten career speedups...I don't even know...quintillion-x on one problem? Not expressible as a multiple. And another thing about me which I found to depart from the norm is I produce tangible research results every time, every single time, total reliability on producing results in research.
And we split the benefits, between computer scientist and manager.
So yeah, so a friend who is a great programmer, which I am not, said yeh it depends some days it can be 5 lines of code some days 500, and they're both good days. A lot of variation, but the 500 lines are unimpressive and the 5 lines are unintelligible, so if you mix them you get the boss happy...sort of. If such a thing existed.
In general bosses are designed--just viewing the org chart as a data structure to extract useful work out of a disorganized mass of people who need sustenance. This is generally done by making a hierarchy ie a tree, similar to society in a closed system (pecking order or popularity in high school) and also similar to the organization of the human brain, all trees--so bosses are by design not tolerant to variation. Bosses want bricklayers. They pay the minimum of effort and value.
In particular shitty bosses of shitty companies, that's the only people open to talking to me after torture ruined my résumé. Which is also apparently most companies most of the time in most economies in most of the business cycle, just not that profitable. Not like they pretend with their gold-plated (contains gold yes but like one gold atom per square inch like any ordinary) dogshit. Just not profitable. You gotta bring them the money to get a cut, they're deep in debt, and it's personal like it's not company debt the boss himself "loses the house" as if it were his when it has a mortgage, but at any rate personalized debt, and personalized liability. Not Options SpA who is in debt. Companies don't exist really. The boss, call him Fernando to give him a name like lets pretend he was my boss because he denied this in court, is in debt. 20% annual interest. Standard for Chile. The banks let them get enough to look rich to a sufficiently accomplished, sufficiently "gullible" computer scientist. As if it were wrong to believe capitalism had merit, born during the fall of the Soviet Union. Stupid to be a cappie, guess I should have been a commie.
There's so many companies that don't add up to dogshit. Like you gotta show up to work the first day with an ingot of gold worth double your salary for the boss to do the great honor of cutting it in half to give you half back.[2]
And they don't let you choose which half.
Being literal here.
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[1] Commie : communism :: cappie : capitalism. But I suppose I can be both. Why not? Be a cappie and a commie? Honestly my life as a computer scientist would be pretty much the same on either side of the Iron Curtain if I lived in the fifties. 99% taxes as a Soviet inventor, with all kinds of privileges like backstage passes and RELATIVE freedom of speech which is huge for someone who wants to be heroic especially during transitions of leadership, and like free travel in a closed country which according to Edward Snowden is so beautiful, plus like a solid budget with an actual pounds (later dollar) amount for a lab to do whatever I dream of, plus access to all the absolute most locked-down information from the whole world for my own enlightenment (unlike the Americans who didn't know dick of Soviet developments in the fifties), it's true liberty. All I have to do is find some merit in some mostly but not completely defective parts--those are always the best.
And on the cappie side of the Iron Curtain, much the same thing. 99% taxes because as an Intellectual Property expert told me there's like thirsty parasites on the way to the Patent Office, corrupt but navigable (every place is corrupt just not every place is navigable), you still pay taxes just not to the orphanages, more like the sugar daddy orphanage of the daddy who isn't even there, paying for golps of state of Iran and Chile same shit different day, unlivable conditions all over the world, and yeah the system doesn't need as many watchmen and trust but secretly it does there are brutal asswhoopings just exported to eg Iran and Chile, and the inventor in the fifties didn't really get his get. The inventor, I repeat, doesn't get his get. Like the guy who perfected FM (frequency modulated) radio committed suicide because the large corporation, in this case RCA (Radio Corporation of America under that Belorussian expatriate called "the General" informally) which had to pay a million dollar fortune to the true inventor's widow, that guy got fucked.
And I got fucked. And you got fucked. We all got fucked. That single inventor's betrayal is the reason FM radio, which is typically the only radio anybody uses calling it radio, is an odd frequency. It's megahertz, "a hundred and one point one" refers to megahertz, and the true inventor originally had "radio one hundred" which saves air time and listener time, lines of code right there, but RCA in response fucked him by broadcasting really loud .1 MHz away from his stations. And they fucked him, fucked you, fucked me, fucked everyone, and that was what the court found and told them to pay the fuck up, give his widow a million dollars for being culpable of the inventor's suicide. That is to say, they suicided him. It actually is a transitive verb, it was in Rome, were suiciding was common at the beginning of the empire. But the inventor got fucked and everyone except that Belorussian defector with him.
In the 1910's America rewarded inventors, in the fifties I don't know man. Like you'd get a job in Bell Labs, attaboy for inventing the transistor. And even then Bob Noyce and those guys had to come up with crazy multipliers over and over. I could almost do that if I didn't get tortured, but I can't survive by multiplying zero by any speedup no matter how astronomical. Zero by a thousand is zero. Zero by a million is zero. Zero by a billion is zero. Realistically you eat half your food to get a 2x multiplier, Zeno's Paradox. That's the most literalist shit there is, Zeno's Paradox.
And of course the big companies paid a lot in taxes, CEO's generally made at most half a million a year, very tiered, 90% taxes at the top, and they were my old time best friends these capitalists, the old timers. Not about snubbing people at the country club as a form of entertainment, more like rewarding hard work. That's it. That's selfish enough for them, compared to that taxation. Lines of code, in a lot of cases.
Hey, no lines of code, no work right?
[2] They prefer exotic metals because gold is obviously money. Apparently time is an exotic metal.
I expect you can't not approach everything this way because you were programmed.
I love it.
I think you're a pretty cool user, Maursault.
Line count is certainly a horrible measure generally, but it may not be a horrible measure for a given (programmer, language) pair, because most programmers have a certain style and may have a fairly standard rate of useful expression per line (or something like that, I just made it up).
However, without knowing either the programmer or the language, just raw line of code count is meaningless. People spend money on software because of what it usefully does for them, not because of the LoC.
And yes, I did read that far.
Tell me what your app is called!
Like is it good? Do the students love it? NEED IT?
Cause if it sucks it sucks. There's a lot of products that suck. I can't buy something that sucks. Flawed I can work with, sucks, like contempt for me, I can't.
Good luck with the acquisition!
As for your app name, that would only happen either by accident or because you'd spammed HN in the past. If you want to say what the name is, I can try to figure out which.
(Unofficial tl;dr: The price is x2 or x4 your last year profit.)
so why not port over to Electron and go multi platform?
Anyway regardless of that I hope this thread itself isn't removed, because it generated good discussion.