I took a long trip to huaraz (2 months) a few years back and I was definitely antsy about the thought of not bringing my skis. I did not regret my decision even once (well maybe once when looking at the SW face of Artesonraju) . Add on the fact that there is a lot more objective concerns with avalanche conditions and bad weather in their summer (rainy) season (when youll be there), I would be very sketched trying to ski any of those peaks without loads of experience down there. As for renting-- quality control is certainly a big issue.
For information on climbing down there i would highly recommend Classic Climbs of the Cordillera Blanca by brad johnson if you dont already have it. its a really sweet book.
have a great time in Huaraz. despite it being the off season down there, its still a really fun town.
