I done 2 walk ups in the 90s, and one about 2008. £25-£35. Which is actually very expensive, if you only last 5min.
With one of the girls i leaked a little before she put condom on. After some negotiation she let me shag her, as long as it was only 5 min max. She said "please dont tell them i let you come twice". Chilled me to the bone, no one talked about pimps then, first i experienced it.
I really avoid them if i can, but sometimes do them on impulse.
As for 1 hour session love these, but just cant afford them.
Also in london there are so many escort ads I cant find one I like.