I've got some thin quilt type throws from Asda and some fluffy blankets. They don't fully cover the king size mattress, but close enough. I make sure anything happens on top of it. Due to the current climate and the need for thorough hygiene, every used cover (plus pillow cases) are put straight into the washer after a client.
I've had the problem with scabies and accidentally shared towels. If I suspect anyone has scabies, I'll refund them and if they've showered or touched a towel, I'll bin it.
Besides that, in winter, I just change the bed. I don't find the bedding from Asda or Sainsbury's creases very easily. It never looks too bad. Unless you get the Egyptian cotton range. The cotton/ polyester mix seems to be hardwearing, I wash my duvet covers every day in civvy life, 3 on rotation. Had the sets for 8/9 months, still going strong and none were over £15.