Have been to Berlin, Germany a lot lately. Here are my deal-recommendations:

Sylter Hof ****. Decent hotel right behind the KADEWE department store. Internet works, sauna doesn't most of the time during the day. Internet costs 12-18 bucks. Got this hotel twice for $ 100-/night incl. great breakfast buffet. Parking costs extra. Downfall is an extremely arrogant front desk staff.

Grand Hotel Esplanade *****. Used to be the best hotel in town before `89. On occasions, rooms can go as low as $ 120, which is a great value.

Steigenberger *****, Los Angeles Square. Can only recommend this hotel if a price below $ 150 can be realized. After two stays, for me it's not an option any more, because WIFI doesn't work in all rooms, and staff keeps feeding people BS-stories about their laptops being not compatible, etc.

HSH Hotel Albergo *, Hohenzollerndamm. Great for small budget. I paid only 45 bucks/night, and it was well worth it. Internet works and does NOT COST EXTRA! Friendly staff and decent breakfast buffet It's right across from the German Social Security Administration, means, after office hours there is free parking on one side of the road.

I book these hotels either directly, or use the page agoda.com (VOUCHER), whatever is cheaper.