When I give the Nan Guest House 5 stars, I mean it's excellent by the standards of budget guesthouses, not by the standards of 5-star hotels. But for a budget guesthouse, it's brilliant. I paid 250 baht for a room with shared bath and fan. The room was spacious, pleasant, and spotless. There were comfortable twin beds, each draped with a pretty Thai textile runner. There were three windows, whose shutters could be left permanently open, due to the impermeable window screens. The two towels had been cunningly rolled and folded to resemble two swans. The bathrooms and showers were clean. The lobby area was attractive. The guesthouse is on a lane well off a main road, so noise is not a problem. They have a cafe across the lane offering drinks and breakfast (Western breakfast only). Prices for beer from the cooler are more than fair. Rattha and Luck, the two women who run the place are very friendly and extremely helpful, with good English. Free, reasonably fast WiFi is available. As budget gueshouses go, this is as good as it gets.

This wooden, old, traditional house with nice lobby and wooden wide stairs that lead to the guests' room is nicely located. It is walking distance to the city centre, the night market, the temples, the museum and the bus station.
The quality of the rooms and baths is not amazing. There is a lack of furniture and space to unpack your stuff or a place to sit. Everything is outdated. This place is good for having a roof over your head for a night or two for travellers in transit to other places.
Nan itself is a very nice, clean, provincial town with friendly people and nice, well- built houses.
The ladies that run the hotel are very friendly and they speak English very well. The problem is that you may see them only for a short time during your stay and the staff that run the hotel in the afternoon and morning does not speak English at all. Even basic, small things become problems because the level of communication is close to zero. The coffee-shop is open when the owners are back at the hotel, so you may have to wait a while for breakfast or morning coffee.
The breakfast and hotel are not cheap considering the location and the standard of the hotel, but there are not too many tourist-oriented accommodations in Nan.