Update
The warnings about the Ibis Budget I took to heart. Thank you. I actually used Priceline and got the Kempinksi Bristol Berlin for $69/night. Online reviews seem mixed but I'll take a 5* hotel for that rate. Hopefully, the rooms are indeed air conditioned (I love a cool room). The website says they have free wireless access in the rooms; the reviews say the online access is slow and expensive. I believe the latter so I'll log on elsewhere. I have questions about the property but I'll start another thread later.