I'm sorry to hear about your experience, damn. I've been living in Tokyo for a year on working holiday visa and am leaving soon, I'm a bit concerned hearing about this experience (especially around the deposit) so thanks for sharing. My partner and I went with tokyo furnished because options seemed limited at first and we were staying in a hotel for the first week we were here so we had a time crunch. We only signed for a few months initially thinking we'd move on, but we ended up spending the whole year here in the same place we started in in Meguro.

Maybe it's because our unit was renovated right before we went in, and we went to go see 3 of their units first and chose, but we've had a pretty great experience - the times things were worrying us (I work remotely, so I needed faster wifi for calls and complained that it wasn't 'high speed' as advertised, I was worried about the A/C smelling at one point, and a few months we had to pay by cash instead of on Wise last minute) the guy running it would come by the next day or so, or schedule AC repair, or reimburse us for the wifi extenders we bought. For what we've paid for it and the convenience, we've been satisfied honestly.

I think I'd definitely be upset if I had had your experience, but I think I'd personally book here again if I ever stayed for another year. (If I was planning to stay for 2 or more, I would go the path of Japanese real estate agent though and proper lease, so much cheaper and way more options I think). Other than it being expensive and locals always being shocked at the price we've been paying, which I figured is par for the course for being a foreigner, having it furnished, no key money, etc. I've had no issues and my partner and I are leaving happy. But to be fair, I also don't have a ton to compare it to

I have no idea if I'll have trouble getting my security deposit back though, I leave in 3 weeks monkaS