May not be luxurious but stick with it for value and location !
Ask for river view and just enjoy it.
Rooms clean but basic. Hot water a bit unreliable.
Breakfast standard continental and is adequate.
Walking distance to everything of interest in Mertola, which is very hilly as you might expect so not good if you have mobility problems.
There is boat and canoe hire when the river is safe. It was very fast flowing when we were there.
Nearby country park is interesting and worth spending some time exploring.