The nature of consulting (no ongoing support) means that most apps built by consultants are trivial. That doesn't mean they aren't talented programmers, but it also means that if you're looking for something that could legitimately be a 10k line Rails App you may want to think about whether it's appropriate to even be hiring a consultant.

Also, a lot of people that are famous for "community work" are the last people you want to be working with in the trenches.