We rented both houses for a family reunion for my wife's family which consisted of 4 adult couples and 2 sinlge adults, plus 9 children ranging from 6 weeks old to age 8.
The homes themselves were great and in the condition described in the listing. I wish I had known in advance that there was no air conditioning but now that I'm talking with others, that's pretty much standard in all of Maine for a rental property so the fact that it wasn't on there certainly does not reflect poorly on the property or the listing itself. The lake is very nice. It's large enough to do boating and other activities without feeling crowded, but it's not so large that there are a million people flocking to the lake for the day and filling it up and making you worry about the safety of children swimming around the dock. And it's a great temperature for swimming, kayak, canoe, etc.
The owners were very attentive to our needs, as we had an unexpected plumbing emergency in the kitchen at 4:30am. They answered our call right away and had a plumber there to fix it by 7:30am, and this was on the July 4th holiday.
The only reason I'm leaving 4 stars instead of 5 is that the write-up doesn't make it clear the treehouse is across the street from the lakehouse. So while it is "just behind" in the truest sense, the write up could leave people with the impression that they physically occupy the same piece of property. There were 10 adults in our group all reading through the listing before selecting a house, and when we showed up we all had the same reaction that the listing made it seem to us that they were sharing land rather than across the street. With young children in the group (even those who are 8), it was unsafe to let them walk in between the two properties without an adult chaperone. The street is calm and remote for the most part, but there were definitely some cars flying down it at 35+mph at random times that would give me pause in letting a child cross the road unattended.
I'd definitely recommend the two homes for groups with mostly older children or all adults, as the distance between the houses is short and for those who are older would have no safety issues with crossing roads.