Reddit mentions of Ubiquiti Networks U-PRO-MP UniFi Professional Versatile Mounting System for UAP-AC-PRO, UAP-AC-HD and UAP-AC-SHD Access Point

I've been happy with my new Ubiquiti network so far. Our house is 2700 sqft, 2 stories, pretty open floor plan, and has an unfinished basement. One AP-Pro, mounted to the 2nd floor ceiling has provided good coverage throughout the house, even down to the basement. YMMV

I understand you are renting and are concerned about hard wiring. If you can get a cable up to the attic, then I would ask the landlord if you can go ahead and mount an AP to the ceiling of the 2nd floor. Sell it to him as something that will make it easier to get renters (or keep you as a renter). It can be a simple installation that can be easily patched when you move out. Drill a small hole in the ceiling to pass the ethernet cable and a few screws into the ceiling for the AP's mounting bracket. A better installation would be to install an old work box into the ceiling and use this mounting bracket for the AP. That bracket attaches to the box, so no additional holes are needed in the ceiling. When you move out, just pull off your AP and bracket, stuff the end of the cable in the box, and put a blank cover over the box. The next renter can then install their own AP there, if they want. This is how I mounted my AP.