Sayo Guest House Xieng Mouane  may not be the top guest house pick in Luang Prabang, but might be worth considering. The upstairs double suites for $50-70 US are incredibly sapcious with another mezzanine bed included and large  bathroom.

(Room A3 but A6 is simiilar)

It also has a great location near to the Mekong River, the start of the night market and good restaurants like Cafe Touri and Kaiphen.

And the other end of the range  are the downstairs double or twin standard/small rooms startting at $20 US.

B3 is a standard twin for $25-35 US.

Breakfast is not included, but can be ordered separately and includes eggs cooked to order, ham/bacon, fruit salad, baguette with butter and jam, juice, tea and coffee.

However the breakfast seating lacks charm and you might prefer to eat at one of the other eateries close by as it is not included in the price.

15% discount offered to groups.