Middle Lodge is near Mintlaw. It's a detached granite house, set back from the road. You've got your own garden and a patio area with furniture.
It sleeps four. Two bedrooms, one bathroom. It's got a 3 Star rating, which I think means it's comfortable and clean without being overly fancy. The living room is spacious and gets good light. There's a separate garden room if you want to sit and look out.
The owner leaves a welcome pack with local things in it, which is a nice touch.
You're right on the edge of the old Pitfour Estate. There are walks from the door through the woods and around the lake. You can walk to Old Deer in about half an hour to see the abbey ruins.
In terms of things to do, the coast is about twenty minutes by car. Newburgh has a seal colony on the sands. For cliff walks, the Bullers of Buchan and down to Slains Castle at Cruden Bay are good. The beaches at Fraserburgh and Cruden Bay are long and sandy, and they're rarely busy.
There are a few castles within a half hour drive. Fyvie Castle is the big one for the National Trust for Scotland. Delgatie and Banff are different, more lived-in. Peterhead has the prison museum, which people find interesting, and the fish market if you're up early.
Facilities: it's got a wood burner, dishwasher, washing machine, TV. Bedding and towels are included. There's a cot and highchair if needed. On-site parking. You can bring up to two dogs.
There's a shop and a pub about two miles away in Mintlaw.
For wider planning, the NatureScot site has details on the local nature reserves like Strathbeg.