In my experience, a more focused product built by investing in testing and iteration is always more valuable (and more successful) than a large-scale app built blind from start to finish.
“Thanks for helping me define my product more clearly, prioritize my feature set and create some milestones. It was very helpful and your process makes a lot of sense, but I’ve found a programmer on Craigslist who said he could do it for a quarter of the cost.”