Perhaps we could work on a sliding scale, where payments are made as the services progress:
- client arrives and agrees that the WG is the one he was expecting: 10% of fee paid
- WG offers a cup of tea: 5% fee paid
- WG undresses and doesn't have a penis: 10% fee paid
- punter undresses: 10% of fee paid for WG keeping a straight face
- WG starts to perform BJ: 5% fee paid before starting, 5% paid during, and 5% paid after
- penetration starts: 10% paid before starting, 10% paid during, 10% paid after
- during punter's climax: 10% paid during build up, 10% paid while cumming
At all stages there would be a minor break in activities, while the money is sorted and the WG stores it safely away.