From my shop's site:
With the advent of companies who sell bikes over the internet in unassembled condition and expect the customer to do the final assembly, we feel the need to educate our customers about what they should expect should they want us to assemble such a bike for them. Although many of these bikes are touted as "90% assembled", they arrive in much the same condition as bikes from our own vendors, which is to say, in need of a lot of attention. All BikeWise bikes get a thorough assembly with all systems receiving attention. This usually takes a skilled mechanic at least an hour, and in the case of a triathlon bike, up to three or 4. Because of our commitment to the highest standards, we offer complete build services, but we do not offer a service where we will do only the "final adjustments". Only by doing the complete assembly can we be certain the bike is safe and reliable. This service starts at $60 for single speed bikes (fender and basket installation extra) up to $200 for high end tri and road bikes.
Bikes previously assembled and ridden are another matter, and if the bike is in good working condition when boxed for shipping, prices start at $40 for a simple reassembly. Multispeed and tri-bikes may be higher, depending on state of disassembly.