You can always try it with others...never hurts to ask. Probably won't work with Crowne Plaza but you can just book your best rate on their site, but they are more in the $180 range unless you want a view of a building one alley width across from you, so beware the $100 rooms you may find...you won't be overlooking Avenia 9 de Julio, and it would be a shame to stay there without that!

Generally, like I said, the Claridge will accommodate you at that rate unless it's a holiday or otherwise a really busy time. All in all, it's an excellent hotel for that rate, great staff, very good food in-room and at their restaurant Full buffet breakfast (American, Continental, and European) is included in that also! The rate ($99 or $95) is on their site right now as a "promotion" but in fact they almost always have this promotion running...

http://www.claridge.com.ar/CH_HotDeals_.htm