If it’s one or two men there for a couple of days, I would advise them to use the loo, and if I am out, I leave tea and coffee making facilities, and biscuits for them.
I would not expect them to take the proverbial and crimp a length off – I think most workmen know the protocol, Number Ones are fine, Number Twos can percolate until they get home.
I have never had any bad experiences, but I have always used workmen that I trust to behave in my home.