Just my opinion here, but i change my sheets all the time. I think if a client asked me to do that i wouldnt, if my sheets were a mess they would get washed anyway and the flat i rent is immaculate!
In Inverness there is so many WGs working out of drug dens....clients should be happy when they come to a decent place.
Guess my point is, if your sheets are all cummy, surely they will get changed anyway. xx