[wkornewald]

In general, it's better to have the team work closely together in one office. If you want to bring in contract developers they should be reachable during the time when you work because you'll probably need to communicate very often. So, the timezone difference shouldn't be too large (USA - Europe is probably too much already, at least for your main developers). Later you might want to have a backup developer in a different time zone, so he can troubleshoot problems while you're sleeping. Also, when outsourcing it would be better to pick someone (or a team) with startup experience.