If you're the sole bread winner for your family, then potentially accumulating a ton of debt is not something to be done lightly.
Test your idea, whatever it may be, before taking the loan.
In my experience this has been the better path. I worked fulltime on an ad supported site for 3 months, plunking 10k into it(and living expenses), and got about $200 in return.
Another site, which I built in a day, has generated over $10K for me in ad revenue. It's a big crapshoot and going full time probably won't increase your odds too much. Wait til the traffic is big enough, not your desire.
A large number of famous startups have started this way--Facebook, Yahoo, Google, craigslist, eBay...
It is incredibly easy on the vast internet to work on things that may be interesting, different, unique, cool, but in the end don't attract a big enough audience to pay the bills and beyond. That's why I think it's dangerous to go full time until you have some site with significant traffic & growth rates.
Don't get me wrong, I'm not opposed to startups going the self-funded route and pursuing revenue from the get go, but that's almost impossible with ads. If you really don't want to raise money, go with the best idea you have that has some other business model.
Beyond that, try to think of creative ways to market the site. Going the subscription route is very hard, but if whatever it is you have up your sleeve is compelling enough you can make a lot that way.
You're in a really good position, and for some reason you seem to be waiting for something...I'm not sure what.
Get out there and build it.
2) You then need to Position yourself in the market that's demanding it. This requires you to develop a consistent profile in the marketplace, so when people think of 'Generic Need' they immediately associate it with 'poppysan' before anybody else.
3) Above all, believe in your business. If you're confident, you will invest emotionally and be productive. If you're not, the market will see you as a frantic mess to be left alone for a while...and you don't have a while!
Which means that building such product is the easiest and (by far) the cheapest part. Promoting something consumer-oriented, building your brand, attracting those visitors will cost you hundreds of thousand of dollars, millions even.
The rule of "build it and they will come" does not apply to consumer-targeted internet-entertainment business. Media businesses require either lots of luck, or massive investments into PR (and still some luck). Digg, Reddit, TechCrunch, even CNN - they all had some "lucky event", something out of their control, which contributed to their boost in popularity. Technology takes the back seat, unless you have something truly groundbreaking, like Google had.
Sorry to deliver the bad news, but your $50K are irrelevant, find some well-connected people to support you. Reddit wouldn't have happened without Paul's PR machine.
When you have a business plan that seems to be working, then you'll have to thing how to implement it, distribute it and so on. These are crucial steps and all beginning enterpreneuers will be far too positive on these so if you think there will be X customers that will pay Y amount of money, divide them by half.
When you have everything planned, you need to think how to finance it - that is when your 50k will come to play.
I would recommend 253% to keep your day job until you have at least one paying customer or are getting some decent money from at least something connected to your project.
Too many projects end like this and it's very, very sad: http://www.snotr.com/video/1133
Here are two suggestions.
First, build something subscription-based that you can finish in about 3 months and 25% of the money. Then support, promote, manage, and improve the site part-time, and get another part-time job. Or sink all your money into initial development, get another job, and manage the site on the side.
Second, build a consulting company instead of a product. A healthy programming/design shop can generate steady paychecks + profits, and you can reinvest the profits in a product. $50K is more than enough to start a consulting company.
then again, you could also try: make people want something.
however, you said you were a programmer and not a marketer.
alternatively: want something? make people.
nobody ever went broke betting on people's urge to reproduce.
permutations are fun: something people make? want.
desire in the world comes from attachment to expectation, we are the fabricators and stewards of that desire. want-creation is a multibillion dollar industry, ads are just the way to tap into that market with the lowest barrier to entry.
wheeee: want something people make.
aggregate other people's content. for text, scribd, for video, youtube, for audio? (i consider this one still out there for grabs.) increasingly, micro-markets (like etsy) are going to flourish, facilitating trade between craftsmen and consumers. make your mother proud, become a middleman.
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for real advice: dont pay an accountant or a lawyer until you start giving other people money or taking other people's money. before you do either of those things, get the go-ahead from both. things take twice as long and come out half as good as you think.
also, make sure there is always forward progress on what you are actually intending to provide. you provide someone with resources something (goods or services) that they perceive as valuable. unless you continue to create more/better goods or provide more/better services, you're stagnating.
I've also got a few ideas, ranging from simple to grandiose. My plan is to start with the simplest (fastest to create, simplest revenue model, smallest potential) as a moonlighting effort. I hope that it can generate enough to keep me alive to buy time to start pursuing the grandiose ideas. YMMV.
It's as simple as that. People will pay for something that they think is worth their money. When I made www.friendfury.com it went completely viral and made $600 the first 8 hours and about $200 a day for a few months afterwards until we stopped promoting it heavily to focus on other projects.
People paid for our subscriptions because it was worth the money to them to get 500+ friend requests a day on Myspace for whatever reason.
The only problem is, I don't have $50-100k. Or even $5k. (Feel free to help change that! :o)