It's a real petty how fast a property can run down.
Sure, the restaurant and beergarden works very well, food is good, it's hard to get a table, it's very profitable - but due to this success they forgot about their 18 room hotel. Some of the front desk staff (incl. the manager) became very arrogant, hotel guest parking place is always full of cars of "friend of owner" (plus you have to go in or call to tell them to open the gate), no room service after 22:30 (not even sandwitch), new hair shampoo is forgotten, laundry not always returned in time (what to do if you're leaving?), standard rooms at € 180,00 are very small, Junior Suite at € 280,00 nice but too expensive for ahotel without swimming pool, 24 hours room service etc.
Plus and Minus is the location: it's directly at the river and it features a nice restaurant, but otherwise without car you're lost! It's between Frankfurt but nearer to Offenbach.
Finally I've to say that at the price charged there're much better offers inside Frankfurt, hotels where you feel welcome.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC