Your problem is your answer, you need to save up 175 simcash to buy the third playable sim
anoymous
How do u get ride of a party and u can't get ride of a roommate at least I don't think
anoymous
Idk sorry I also asked the same thing
anoymous
How do you get rid of a roommate
anoymous
The third slot indeed costs 175 sim cash. When you unlock it you can choose to either create a new sim, or to make an existing sim playable.
You'll need another 515 sim cash to unlock the 4th player.
anoymous
The answer is actually in your question. You spend 175 SimCash to unlock the third playable SIM, at which time presumably the game will reveal the price to unlock the fourth slot.