For anyone that knows me, you know I love tiny houses I think they are adorable. My future house cannot be bigger than 1,400 square feet and even then that's pushing it. I hate cleaning so this would cut down on that. However, I think you would have to be very comfortable with your partner. There isn't a lot of space, so they would hear everything.
It would definitely save money, though, especially since I plan to travel. Of course, Christmas and Thanksgiving can never be held at my house but that's a good thing. It's definitely possible to get what you want in a big house with a tiny house. A few of these houses have a wraparound porch, a deck, libraries, and/or large beds.
This apartment in the picture above is a 240 sq foot apartment in NYC. I am pretty sure what is in the picture is basically the entire apartment but I'm also sure since it's in New York it's way more expensive than the average tiny house.
Here's a tour of tiny house.