I recently went with this company that deals in computer repair in DC when our network of computers went down in the office. I was able to get in touch with a representative and they set an appointment up for an engineer to come around and solve the problem. I do think that their customer service department should specialise in faster replies, but the point is that they sent out a team in a very short period of time. I also believe that their team are amongst the best in the business as they were able to simple complete the job and then explain exactly what went wrong.
http://www.geekabc.com/PC-computer-repair-DC-Baltimore-potomac-Maryland-MD.html
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