| No, you can do this yourself. It's very easy, but not as easy as doing it on a guitar IMO (which is probably why people say it's hard). I would invest in a key crank (you may see them advertised as a string winder) to avoid a lot of hand-twisting, and most also have a wire cutter on the end.
There are plenty of how-tos on the Internet, and really the only thing you can do wrong is cut the string too short. You should generally have between 2-3 inches of extra length beyond the tuning post when measuring the string out to cut. Keep it closer to two inches for most tuning pegs, but give a little extra for wider posts like the ones Fender puts on their MIM and MIA four-string basses. You should end up being able to wrap the string about twice around the post. Getting three or four is generally OK on most tuning pegs and for the narrower strings, but don't overlap windings; that affects tuning stability. | 
