It is a shame that this place isn't more famous! The more you learn about it, the more you realize what a building of great historical significance it is.
I happened to be there during one of the twice-weekly tours and was able to hear a detailed explanation.
We didn't pay to go into the house but enjoyed the garden for free. There's an Inari shrine with vermilion torii gates, and a pretty lake with a bridge that reminded us of Monet's paintings and his garden in Giverny.
There's a tea house, too, but you can only look in from outside.
The azaleas are beautiful, but were mostly finished when we were there, while the wisteria was not yet in bloom.
It was a super nice place to visit. The building is well maintained. I liked hearing about the owner, who is the creator of the matzukaiya stores that are in all the stations. The north garden was also good. It was awesome to hear how they connected a lot of the building via underground tunnels. The staff were nice and for 300 yen it was a nice place to explore while in the area.
Slice of history and not crowded with tourists. Very well kept luxurious villa + gardens. Really easy to walk and explore. Children and elderly friendly.