Not far away from Konoha, within a secluded part of the forest, there stands a mighty tree beside a bright blue lake inhabited by very particular breeds of fish and amphibians. Said tree's large branches occupied by something which cannot be described in any way other than a lousily built tree-house-mansion. It was massive and accessible through many unusual means unknown to those who were never informed of them. To the eyes of a stranger there wasn't even a door to be found! But there were many windows of many shapes and sizes. Unfortunately though they were always blocked by thick curtains.
There was one entrance of which almost everyone in Konoha knew, a hidden staircase in the trunk of the tree which could found by pressing the trunk in the right location marked by bird-like grooves in the bark; causing a doorway to reveal itself.
Inside, the residence was even more of an absurdity. The layout seemed to defy all logic as there was a basement and an attic, there was rather spacious room cramped with books and desks which was his private library made public to any and all Konoha residents.
His personal study was guarded by a statue blocking the doorway which only moved when speaking the correct words. And would aim to swing its stone sword down onto those who tried to bypass otherwise. (Over the years leading to several bruised academy students and even adults who found themselves getting patched up by the medical-nin back in town after impatiently trying to bypass the statue known as Mr Stone.)
His bedchambers were hidden by far more peculiar means and protective measures. Here he kept his most precious items, his treasures. As well as several books of extreme rarity and his diary which was filled with many ideas for Jutsus, wild theories, and entertaining stories of everyday life.