A bit offtopic but: I have been always scared to work with co-founders even if I know them, but looking for random people for the web looks way too scary.

Not because someone will do some nasty things, but because there is a high probability that there will be disputes about how to do things, which will lead to break up?

When I was looking for a coach in gym, at first I attended the gym for a year and I was silently looking at coaches there, how they behave, how they talk, and only after that I decided to hire the one who suits me most :)

Anyway, wish you luck!