This could be the cheapest quicky bar in Bangkok, with short time rooms at 250 Baht, and Barfines at 400, suppose you give the lady a 1000, total sets you back for 1650 THB, Fannys at Soi Cowboy has an outside seating area as most bars in Soi Cowboy, a few nice and a few ugly/older girls, bu still worth a visit.
BARFINE: 400 Thb
Adress: Soi Cowboy