No pictures of this Onegai location, only crappy sketches by me and a picture from Uminokuchi station. The same person who gave me a ride towards the top of the mountain also showed me the Maiku House. He said that taking pictures was not allowed. You probably need the permission of the owners first.
Because the village is so nice, I won't post any pictures of that house. I did make some pictures of the Maiku House when I walked around the lake in the morning, I guess I can keep the pictures I made before knowing that no pictures are allowed. Will keep the pictures for myself only.

A small detail I noticed while making sketches of the house; in reality the west side of the house only has one window, in the anime it has two windows. Also a balcony is missing in the anime. Maybe the Maiku House changed a bit over time (5 years is a long period) or maybe the creators of the anime didn't make a 1:1 copy of the Maiku House.

Anyway, this is the house where Maiku, Miina, and Karen lived in! One of the scenes in the anime Onegai Twins I can remember very well, maybe because it appeared in every single episode. It's a nice house with a great view on Lake Kizaki. About 3 minutes of walking from this location is a small shrine, also part of the Onegai Sites Tour.