Your investment in a new Ystore.com project runs usually between $2500 and $4995 for design, development, & consulting with a few additional expenses in the initital marketing push for directory listing fees, PCC initial accounts, domain name registration, etc. We usually get a deposit of $999 to begin the project and spread the other payments to coincide with specific benchmarks and deadlines along the way.
You get a package price for my experience, brainstorming, research, store development, action planning and implementing the plan, as well as a block on my calendar every week.
Another way to look at your investment is what some folks pay for traffic. Think of this spin-off projects as the same thing as buying about 20,000 pairs of eyeballs because that's how many folks you would get with your $5000 from GOTO/Overture at the average price of a TOP-3 positon at .25 per click. Remember: All the traffic that comes after the site has paid for itself is gravy.
(Some people are concerned about Return On Investment. I shoot for 100% within a year or the project is a flop in my eyes. Anything faster than 13 weeks is a breakout hit and needs to be juiced.)