We were a middle-aged U.S. couple in Berlin for the first time. Stayed 8 days here, very happily. It was a very clean, safe base for going all over the city. An excellent value. The hosts were very responsive and easy to work with.
With two subway lines running through the easy-walk U-station nearby, the whole city was easily accessible and often quite quickly, including the center of town (museums, historic sites) and the cool neighborhoods (like Kreuzberg and Prenzlaeur Berg).
The price and description were very fair for the apartment. It isn't a place you want to hang around in much, because it is a ground-floor location with no views. It's also doesn't have much in the way of "extras" you might find at some airbnbs -- cheese, wine, treats. The bed will be considered small for a couple used to a queen or larger. None of this is a criticism -- just offered for comparison to other places you might have stayed. Again: Price and description very fair. We were pleased.
So, in summary, unless you were looking for a super-comfy place to hang out in, this place is highly recommended by us.