I do keep a variety of sizes. Speaking of cock size, I have seen men for whom even the smallest trim size is too big!
The biggest I ever saw, girth wise, was like a can of coke. It was simply impossible to have sex with him. The guy told me he had only managed sex with one lady in his whole life. It had been the cause of ruined relationships for him.
I suppose when you make your booking you could ask the lady if she could buy some large condoms if she doesn't have them already.