Moved into a new apartment, bad fruit fly infestation

Hello everyone.

This is my first apartment in Albuquerque and I moved into a place that after the first tour looked very clean. I checked practically everything, the apartment was remodeled prior to my move in with new floors, cabinets and fixtures but 3 weeks since moving in I have an almost unbearable fruit fly problem.

I've taken precautions that I thought might solve the issue, cider traps, fly paper, and keeping everything clean (cleaning surfaces twice a day now). On top of that I have no garbage and haven't brought anything more than take out into the apartment and disposed of the garbage right away. I don't have anything that these flies could be feeding off of and I can't figure out where they are coming from.

My only guess is it is my neighbor and they are coming through the vents but the AMOUNT of fruit flies makes me think otherwise. I've ruled out the drains and presently I am in the process of dumping gel down the drains just in case, my next step is install bug screens over my vents. Does anyone else have any ideas? If not ideas what to do?

I contacted the landlord and they sent someone to "spray" but I don't know what they used or if it was anything other than a can of raid around the perimeter of the apartment.

Any suggestions would be pretty awesome. Its a great spot so I'd rather solve the issue here rather than moving out, though that would be last case scenario if I can't take care of it.