This is one of the worst companies in the DMV area. They are exceptionally rude, and inconsistent and scam their customers. Advanced Building Services specializes in contracted work for condominium communities. Most people that hire them have no other option as their condo board requires an approved company to do work on the units. My building unfortunately is stuck in a contract with them and we are fighting to get out of it. Here is just one example of how they scam people out of money while they are already being paid for a job. As I previously stated, my condo hires ABS and in particular, Jeff L. to do work on the building for 3 hours per day. I am a landlord at this building and one of my tenets informed me that she smelled gas in the building. I spoke with the front desk and they said that Jeff would check on it. About a month later I receive aggressive phone calls from Gloria W. asking me to pay them $190 for this incident. I spoke with Gloria and she was extremely rude and demanded the money. I refused to tell her where I lived or further contact information for myself, as I felt she did not need to know this information. It got so bad that my lawyer had to send her a cease of contact letter. She is now still threatening me with the $190 bill that Jeff charged to my unit. Let me be clear, Jeff is hired to do work in the building and this should have been included in the pay that he already received. I have spoken with the building manager who informed me that ABS is a very difficult company to deal with. She informed me that they recently changed ownership and are having major issues within the company. From my understanding, many other condo buildings are also reconsidering their contracts with ABS as well. Furthermore, other owners in these buildings have had similar issues. I have no other choice but to pay Gloria the money that she demands and take action within my condo boards assessment of firing them. Hope this review helps anyone else who is considering hiring ABS. The previous positive feedback about this company was likely from before it changed ownership.