@Erinç1 I don't really see how a little playhouse in the yard poses any more risk than a child getting hurt inside the house, or falling when running across the yard. I might stay away from playground equipment, unless it's quite simple and difficult to fall off of. Kids would love a playhouse, and probably so would the parents- some adult time while the kids are busy out there.
And a basket or box of toys if you are going to cater to families, for sure. A friend of mine who hosts a private suite in her home has that- both the kids and the parents are always appreciative and it leads to good reviews.
But you should sterlize the toys between guests, or have a couple of boxes that you can switch out while the other sits for awhile, due to Covid safety.