First of all, we got an appartment on the third floor, and there was no elevator !
We checked-in, moving our luggage up the stairs (3 floors!) and went for a stroll in the centre of Heidelberg. When we returned to the hotel we found a man painting the walls of our apartment, and with his limited english he asked us to wait a few minutes until he finished ! - Fortunately we had not unpacked, so it was easy for us to get our things and leave - to the hotel's credit they arranged for us to move to another hotel.
In the best circustances, one can claim that this was a result of lack of organisation - although a certain degree of stupidity could also come into the picture.
Another negative point is that the hotel's staircase joins the hotel with a japanese restaurant, and there is a distinctive smell inside the hotel.
Overall, the hotel's location certainly cannot make up for its lack of facilities (lift) and problematic organisation.
Just the location - but it does not suffice.