I just returned from another house-renting vacation with extended family. We've done this twice a year for the past several years. Always rented from a local property management agency. Yes, it's more expensive than renting directly from the owner, but it adds a level of professionalism to the transaction (with one exception-- see below). We've been satisfied with all but one of our trips.

The one bad experience occurred with a house that had recently been passed to a new management company. The property itself had glowing reviews from past tenants, and I could see why. The house itself was a stately, 100 year old property. But houses that old have quirks, and the new manager didn't know how to deal with any of them when things went wrong during our stay. Since then I always ask, "How long have YOU managed this property?" I discount reviews written about stays before that.