Talk

Can you get them a big box each and make a memory box for them to keep all of the tat in? Then maybe decorate in their favourite colour as a nod to it still being their space in your house.

When mine left what they wanted to keep went with them, some stuff got boxed and put in the attic and the rest got rid of.

We haven't turned their rooms into bedrooms as like you we have a guest room, we've turned them into spaces we'll use.

One is a man cave with sofa bed, record player etc It's decorated with stuff I don't like but H loves. Records and film posters on walls. Ornaments of iconic film characters etc.
The other is a doing room. Ironing board left up, sewing machine in a corner, clothes horse for drying clothes. A little tv to watch when ironing. It's lovely not having to get the stuff out all the time and it's all being dried and ironed close to where it's put away. It's a great space.