Some of the advice above is good, but not complete,
Yes inform reception you are a prostitute and they will give you extra towels, but also ask them for discount as you will be bringing lots of trade to their hotel.
The flyers and posters are also a good idea but you should also have magnetic advertising signs for the side of your car, and park this as near reception as possible, and put a poster on th ehotel door as well as reception.
Also worth considering is going into town in a bikini and handing out flyers offering your service, that way guys can see what you look like before they book.
Also worth introducing a loyalty scheme, say but two get one free, BUT be different and give them the first punt free and then they pay for the next two