Crowd testing - job for vinay kumar

Hello, Although our marketplace is not 100% completed, we think its time to make a crowd testing of 10-20 different persons. Which questions should we ask them? You must advice us. Of course, we have a collection of some questions, but we might have forgotten something (in fact i made the collection alone, so it's pretty likely i forgot some) If you have a team of 10-20 people around the world, please make your bid (i wont hire an agency who just asks the employees) Thanks and regards