This is Saint Martins House in Tranent. It's a detached, recently built house. It sleeps twenty people easily, which is why it gets booked for big family holidays and group trips.
Inside, it's laid out over three floors. There are twelve bedrooms. Seven of the doubles have their own ensuite bathroom, and there's another shower room on the ground floor. So, seven bathrooms and an extra shower room in total. It's rated 4 Star.
The main living space is all open plan, kitchen, dining and sitting area. The kitchen has a big range cooker, dishwasher, and an American style fridge freezer. There's a second cooker in the utility room, which is useful if you're catering for a crowd.
Tranent is a small town, so you have shops and things very close by. But the house itself is quiet. You'd be surprised how peaceful it is in the evening.
East Lothian is good for golf. Muirfield, Gullane, and North Berwick are all within a half hour drive. Edinburgh city centre is about a twenty minute drive, depending on traffic. The coast isn't far, maybe fifteen minutes to places like Longniddry or Seton Sands.
For facilities: you've got parking, a garden and patio with a BBQ, WiFi, and a washing machine. Bedding and towels are included. There's no gym on site, despite what the facilities list says. There are local options for fishing and horse riding. No pets allowed.
If you're planning trips, these sites are useful: National Trust for Scotland East Lothian for local properties and Visit Scotland for general information.