Having the "best" name doesn't really help you build a brand.
So, if the domain is serving $2,000 of ads every year, it's worth $2k using a common estimation model. You don't want to buy it because it's priced at its value. Yes, you would have a good ROI if you held it, but the ad revenue isn't guaranteed, you have transaction costs, annual costs, etc.
If you know you can double the ad revenue to $4k by changing to another provider or using a proven method of placement, then it's worth $4k to you. If the seller is still offering $2k, then you have a good deal and you should buy. If the seller realizes this and raises the price, then you have to decide how much beneath $4k you need to go to make it worthwhile for you.
If you want to build a business on the domain, then you're pricing the value of each visitor. Let's say each visitor brings on average half a cent in revenue: 400,000 visitors brings $2,000. How well will your business convert these visitors? Say you can convince .05% of them to purchase software at an average lifetime value of $100 -- that's $20,000 per year in revenue. Of course you'll need to build a sales site and the product itself. If that takes $15,000, then the domain is worth about $5,000. It might be worth more since the product and the site could be transferred to another domain, so possibly you could pay up to $10,000 or $15,000 for the domain.
These are just considerations - I don't know the numbers for your business or for the domain you're considering. You would certainly want to choose at least two domains and play the sellers off of each other. Your math might tell you that you'd pay $100,000, but market pressure might bring it down to $50,000 anyway.
P.S. If you are buying for the value of the name as a brand, then I think for that money you should just buy an actual brand.
When looking for domain names I found one that was on sale for $100k, simply as a joke I offered $10k and they accepted this. Obviously I don't even have that but it probably means you don't need to pay so much. Most people look at how much domains were worth in 2000 and think they can start the bidding at that price.
If the name is still for sale and they're willing to sell it, it probably isn't worth what they're asking for it. If you can find someone with experience in the space that you trust, this helped me a lot. Traffic is also key in most names, unless they're a short one word .com they aren't worth much without a lot of traffic.
Worth 100k? Depends on the name. But I thought after reading all these negatives, I feel like many of these people haven't actually owned any good domain names and seen the value that can generated from them.
If you are going to be raising investment from Angels or VCs, are they going to look at your domain purchase and think this was a wise investment? Or are they going to think you were being frivolous with money?
Will the name actually have a significant affect on your business? You'd be surprised how many great domains are still available.
Do you think you could flip it? If the domain is only valuable to you, it probably isn't that valuable. Do you think somebody else would want the domain if you decided not to use it? Or would your money just be gone?
Just a few things to consider.
There are definitely domains that are worth millions of dollars, but there are far more domains that are worthless.
A good point to start is by saying "how valuable would this domain be on the open market at auction ?"- if you don't know you can get specialist with expertise in the domain market who can value it for you.
The simple fact is that nobody cares any more. It's more common to directly type the company name in the address bar of a browser than to type out "www." etc.
What happens when you want the associated .net or .org? Trademark rights been checked?
You could've gotten a .com, net, .org and like 10 years registration for each and been in a good position. And been in a position where you'd still have a lot of cash in the bank.
You have bigger problems here.