First thing to say: the hotel is located right inside the 'shopping area' of Frankfurt, that's a great location. But...the hotel is not opened 24 hours and at midnight it closes. If you check in after 6pm you have to contact the reception to tell them (please note if you send them an email they'll hardly reply or confirm reception of the email as they did to me).
Entering the hotel you'll find a nice receptionist, that is at least 85 years old and speaks a poor english (all mixed with german).
Breakfast is clearly not fresh, eggs are badly cooked and they have a strange colour, didn't trust them. Bread smells bad.
If you think you can eat fruit at breakfast, please be advised they only offer lemons and apples.
The cleaning woman does not empty tashbins.
The window of my room did not allow seeing outside, that's very uncomfortable, it was covered with that un-transparent adhesive plastic. But it was even worse opening the window, just putside you would find a little (about 1 meter per side) squared area, inside an internal 'garden' of the building, closed with an iron net and definitely dirty, there were insects and spiders.
If you look at the pictures, please note the 'emergency exit' table indicates the window, so to access it...first remove the tv, then open the window, exit in that internal area and find a way to remove the net to escape (see pictures) I would define it an 'emergency trap' instead of an emergency exit.
From what I've seen I stronly suspect the room I've got was a service room (like a cellar) adapted to be a room, but furnitures were poor, the harmchai has no even the door and the little harmchair is even filled with their things, books of hotel management. The door is poorly closed, everytime someone else in the corridor opens or closes another door, it moves and is very easily opened. During breakfast, the 'morning' receptionist smokes inside the kitchen.
Just to finish: no internet access.
everything costed around 66 euros per night for a single room, definitely too much for a place like that!
Frankfurt is a lovely city, with great shopping opportunities, I'll definitely be back in Frankfurt, but I won't go back to hotel neue krame.