unlike @KStockHERO I want bar soap in the loo room. Provide both. But a decent-sized bar with a subtle pleasant smell, and make sure it hasn't been allowed to build up residue wherever it sits.
Clean towels, hand-sized (I don't mind there being big towels there, but it must be obvious that the hand towel is for hands). Fluffyish is nice but make sure it's absorbent.
Simple and obvious bolt on the door, that works smoothly in both directions.
And yes, spotlessly clean (at least to start with
).
Apart from that: no cobwebs, dust, dirt, clutter. Obstacle-free path to obstacle-free seats. Ornaments and photos selected for display, not just crammed in everywhere. Any plants or cut flowers well-kept.
Room for guests to put their bags coats and shoes (if they're taking them off). Coasters placed near chairs. Fresh-looking cushions.
If there are children in the household, there should be tidy evidence of this - low bookshelf of their books, photos, their art on the pinboard, that sort of thing.
Incidentally, I have had a particular house in mind while typing this post. It's not mine.