Congrats. Sounds like a great deal.
We basically picked up a free house last year too. We had tear down on the HCOL side of the lake and swapped it for a 5br/7ba 5500sf house of the LCOL side of the same lake, for approximately the same price. Property taxes here are the same for the nice home as they were for the double-wide in the other county. We're 15 minutes further from downtown Charlotte, but rarely drive there anyway. Our electric bill is a lot higher now & we also have an HOA fee, but I'm still calling it a "free house". This side of the lake is beginning to see a lot more development, so I expect property values will increase quite a bit as the roads get widened & more restaurants are opened. A new brewery just opened a few miles South & a new Publix grocery & retail development to the East, so it's already happening. It's been sort of strange moving from the cheapest home on the street to the most expensive home on the street, in a nice way.
I admit that it's way more house than we need, but after shopping the entire lake & viewing all the homes in our price range it was the best value, and offered most of the things we wanted. It has a nice view, a large private lot, master on the main, terrazzo in the common areas, lots of outdoor living spaces, etc. We never planned to live in a McMansion, but they're not so bad if you manage to find a free one. ;)