My wife and I stayed at Cuong Long for 2 nights at the end of January. $20 for a standard double room. Very good location near the thick of things but still quiet at night. The first night I think we were the only guests at the hotel. The second night we saw one other person. Not their fault per se, but it made for a slightly depressing vibe.
Bathroom was decent, hot water and a separate shower section so the place doesn't soak when you bathe. Breakfast is not included, but you get a nice fresh tropical fruit plate every day that we enjoyed. We received fun varieties such as sapodilla, star apple, dragon fruit, rose apple, and mango.
My biggest issue with the room was that the bed was very difficult to sleep on. The "mattress" is just a big piece of dense foam. Other minor issues: (1) The bathroom smelled of mildew. (2) We don't really use TV, but if you care about such things, the TV was minuscule, maybe 13 inches.
The staff were very nice and had a passable (if weak) command of English, but we had a number of unfortunate miscommunications. For example, we asked if we could have more soap, and the staff said "we don't supply that." I was very surprised, but he insisted that we need to provide our own. We went next door to AMart and got a bar of soap. When we came back, he saw what we had bought, realized what we had been asking and then showed us that there is soap in the room and he will bring more up. He had thought we were asking for something else (unclear what). On the plus side, they never tried to push any tours onto us.
Overall it's an average room typical of the ~$20 mini-hotels in Nha Trang, and there are certainly places in that price range with better beds and atmosphere.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC