1. Well for massage girls, it all depends on the girls, some will go as far as a BJ, some will just give you a handjob... Some will give you FS... So you just have to go and check by yourself! It's not very accurante.
2. For some popular gal, it's better to book a slot before going there ! But otherwise, a walk-up is walkup, so basically just go and check the door, instead of trying sms, try whatsapp, usually the number displayed on 141 is linked to a whatsapp!
Good luck