I have a similar question. I can't put the sheets onto the sofa bed and still leave it in the sofa option. It has to be done by the guest when pulled out and made up into a bed.
My question is this: I leave all the sofa bedding in a basket in the bedroom closet...bottom sheet, top sheet, duvet and 2 pillows with pillows cases on. This makes it easy for guests who use the bed to carry everything in one go and make up the bed. It also makes less work for me, so I don't have to remove it all when not needed, and bring it back when needed.
However, I have had a few guests in the last few months who have slept on top of the actual bed's bedding (comforter and sheets not removed or slept under at all, but I still have to wash and change the bedding regardless). They have placed the sofa bed bedding on top of the comforter and slept with that. Which leaves me with 2 sets of bedding to wash.
As I would normally be washing one set, adding another isn't the issue. It's the unnecessary wear on the sofa bed bedding, and the inconvenience of having to spend the extra time putting 2 sets back together.
To me, the easiest thing would be to just keep the sofa bedding out of the suite unless the booking specifically indicates both beds would be needed. Just wondering if anyone else has this issue and how they deal with it?