Went for a rub in classy suburbamn hotel. I knew exactly what I had in my wallet and went to take a short 2 minute shower. Wallet was $80 lighter. Beware
Do you bring complete wallet to a meeting or else what do you bring?
Some folk say they leave wallet in their car. Isn't that more risky than bringing it into a meeting?
How do you stash your stash when you shower
I've never had a woman steal from me. At least not in the U.S. In places like Costa Rica, however, you should always lock your wallet and passport in the hotel room's safe, which is easy to do because everything there is outcall to your room.
Which are: her donation, your driver's license if you're driving (and you can leave that in the car). Leave the rest at the office or at home. Frankly, the DL is the biggest pain in the ass to replace if it's lost or stolen. What are you carrying that would be burdensome to cancel/replace?
Not that I've ever had anyone check, but then I also have a picture of myself in my P411 profile so they know who to expect.
In answer to the original question, I myself usually leave the wallet in the car and bring in only a drivers license and some additional cash (enough to pay for an extension if needed). I'm not at all worried bout theft, more about dropping things out of the wallet in a hurry to shed clothes. 
Which usually means a specified amount of cash, a few condoms, and my car key. Initially, this was based on fear of having something stolen, but now it's mostly a precaution against leaving something behind by accident.
Went for a rub in classy suburbamn hotel. I knew exactly what I had in my wallet and went to take a short 2 minute shower. Wallet was $80 lighter. Beware
That you wouldn't leave in the reach of any other stranger.
Lots of things can go wrong. You might drop your wallet at her hotel. Friendly inn keeper calls number he finds and leaves a message. Perhaps your SO picks it up.
The lady rips you off, can happen. She may have a partner that corners you in the hallway. You going to call the cops?
DL and your money is all you need
Don't forget your car can be stolen or broken into while you're in the hotel. If I hide my valueables, I do so before arriving at the hotel.
I shower before leaving home (a luxury, coming straight from home) and it's soon enough that a shower is not required. If I did, I'd take the wallet into the bathroom with me.
With favorite ladies, I carefully empty my pockets (as I do at home) before undressing... typically I place my pocket junk next to my clothes or even under them. When I redress, I put everything back in my pockets.
Some thieves, pickpockets & scam artists are very good at it.
I recall one story... A guy was recieving a BJ on the edge of the bed & had a funny feeling. While she was in the bathroom, He checked his wallet & discovered the theft. He figured it must be under the bed or mattress... found & recovered what was taken. When she returned she planted herself on the mattress to prevent him looking (but was too late). He got out of there & never went back.
usually put it in my glove compartment even before I leave the house, so less fiddling around as I pull in a the parking spot.
Have everything on me that I need (envelope, fav condoms, breath mints).
In Ye Olden Days, many incall apartments and AMPs would provide a plastic zipper closure cosmetic bag. Empty your pockets or whatever you want into the bag and take it with you into the table shower where you can keep an eye it. Then back to the room where you still it's safe and not tampered with.
These days, I guess you can just use a large Ziploc bag but I don't even bother at the places I visit: I've never had a problem, at all
and leave it in my pants back pocket. I make it a point to never let those pants out of my sight.
and your clothes/personal items at arms reach with bathroom door closed when you shower.
I take the donation and my cell phone. if she wants proof that I am who I am, she can call the cell phone because I have given her my cell number during her screening process.
The wallet stays in my car... in the golf bag which is in the trunk.
if by chance I lose the cell phone, the person who picks it up will have to know the 10 character passcode to enter my cell phone.
If you are bold enough to take the risk of entering this illegal hobby, then I don't think you should sweat the infitessimally small chance of your car getting stolen while you are on a date for an hour or two. Though yes, that would be quite the double wammy if you lost both (and heck, maybe while you ran to the spot of your missing car you might fall and break your arm too, and with no ID or insurance info with you the emergency room might not take you - yes, that WOULD be a truly bad day! ;o)
Just leave it in your car, and go have your fun! No worry.
NOT TRUE! There are those who "just happen" to watch hotel lots for guys going in on the hour, & target their autos for thefts. Which is why previous posters suggested not putting your wallet in the trunk when you arrive at the hotel.
I noticed a Black & White patroling the hotel lot as I was going in to meet my date. It creeped me out, but I was out of the car & kept going with my small gym bag with my gifts. I mentioned it to the gal & she replied that the hotel has requested extra patrols because of thefts from guests autos
When I first started I used to leave my cell and wallet in the car. Reasoned that it would minimize the chance of getting something stolen from me. Until one night I was visiting a gurl who lived in an apartment complex -- and my car got towed while I was inside! Thankfully they let me back in, called the tow lot to verify they had my car, and then called me a cab. And the cabbie was patient and waited for me while I got my car out of the tow lot.
Since then I always take my phone and wallet. Just don't leave them out of my sight. I get a little nervous at new AMPs but otherwise all is well.