Am I required to host every POOSHer?!
No. That could be a lot of hosting! As a build project host you are able to view all the profiles of the POOSHers that contact you and accept a request from those who you feel will work well with you and your project! Think about what tasks you have going on throughout your project and inform those POOSHers of a more suited time in the future to contact you. It's important to keep POOSHers busy - try not to have too few on site so that big tasks can't be achieved but likewise, dont have too many POOSHers so that people are standing around!