Many phone repair companies offer either at the business or home service as well as a drop off repair service. If you are sure the problem is in the phone the drop off service can save you the cost of the service call, but if you aren't sure if it is your equipment or the wiring, it may be worth the price of the home visit to confirm where the problem actually is.
Phone repair for cell phones can be costly if you have them done by the professional company that provided you the phone. Find out, though, if the phone has a warranty or if they offer an exchange policy on the phone that you can take advantage of.