Same as other have said!! you can never be too careful!
do you homework, even if you a friend to ask around or "spy on them" well which is illegal! but it pays! some even work for drug dealers the illegal ones! so watch out!
But it more easier to hear about the rumours with the ones working with drug dealers! even the newpaper and internet is your friend, look at any past cases unsolved etc in regards of bad mistress!
But most likey for a stich up would happen out of sight like indoors or an alley way etc!
But better to meeting in a good public restaurant smart dressed! yeah I know spend money on dinner, but gives you a great chance of seeing the bird, and gain "Trust", of course if you have a friend sitting near by with his partner which he & she is dressed nice, "the mistress" shouldn't have a clue. If you have another friend near by that likes walking his large dog at night, he could have a nose around the alley ways for anything! etc! dogs are good at finding people in the shadows!
If the mistress goes to the "restroom" you stroke your hair back, handsign to your friends partner to follow her 10 seconds later, to "take meds" etc! if the mistress is making a setup! she stoke her hair coming out, or the all clear she rubs her leg at the table, of course if its trouble your friends leave and talk outside! and your male friend comes in and by the toilets his takes off his shoe a sign for come into the restroom, then all you have to do is spill a drink on yourself! and find out what going on!
And make a good run for it! or confront mistress about it! I would pay my friends dinners and the other mate with the dog a £100 for their time and dinner then be mugged!
But if it was a setup and you go outside with her down an alley way, you still got you mate with the dog! and two friend in the car park! and you don't claim to know each other if the police are involve just "good people helping"
Yeah I know others think I am paraniod and a fool, but you be a bigger fool for being mugged and blackmail at the sametime!