Here's my two cents... Do you want to keep this person a a friend? If so run away from this crazy plan. Never get into financial obligations with friends. People by nature are greedy and will take advantage of friendship to get whatever. If you want to go into business you need someone you can trust but also someone you can make business demands to and not worry about hurt feelings.Myself and a friend are equally investing into
As to the specific question if anyone is working then they should be paid for their work so no it's not unreasonable to expect wages.