Mert's place is an excellent place to stay in Istanbul: great location (a matter of seconds off the main shopping street in Beyoglu), nicely decorated, and spotlessly clean. The check-in process couldn't have been easier, and though we only met briefly on my way out, Mert was a generous and kind host. My only regret is that I wish I'd made more of the roof terrace! The only issue that I can at all think of is that there a quite a lot of stairs to get to the apartment (it's on the top floor), so if you aren't that mobile it might be a struggle. But overall, this a great place and I'd definitely stay here again.