So I'm looking to buy a condo and this particular condo we've zeroed in on has HVAC issues to the point where we should plan to replace it within 3 years if we were to purchase. The seller, instead of replacing it, opted to purchase a warranty for the HVAC unit good for a year as of April or May with a $75 deductible and ~$500 extension yearly (I'm hazy on the other specific details for parts/labor). It's a building built in '03, so I'm curious if replacing an HVAC unit generally consists of the actual unit or if the airway ducts might be included as well. If anyone has any expertise or prior experience with HVAC units, any insight would be appreciated. And for those of you who want to share you generalized home-buying advice of do/don'ts/major [uck fay] ups or let me know about things I don't know, I'd really appreciate it so that I can come back in 2 years and kick myself for not listening.