Depends on what your needs are. You can usually buy a complete trike for less than the cost of a build-up. However, just about anything you buy is gonna need work. The advantage of doing a build-up is that you get the chance to go over every aspect of the machine as you put it together, and you'll end up with something real nice. It does take time and $$ though! In the past I have bought parts bikes and made one bike out of several, then sold the leftover parts to recoup some of my expense. Takes time though!
[FONT="Palatino Linotype"]~My Rides (to name a few) ~
1986 ATC250R, 1985 ATC350X
1985 ATC250R Missile (90% done)
1983 ATC185S
1999 TRX416EX
2003 Honda CBR600RR
1990 Yamaha Zuma
1985 XR80 w/100 motor
1967 Honda CB77, '65 CL77
1962 Puch 250 SGS
1984 XR350R (owned since I was a kid)
1972 Suzuki T350 Rebel, '73 T500 Titan
1964 BSA A65 (needs restored)
1968 BMW R60/2 mint original bike
1976 Kawasaki KH500 triple
Anybody have parts to trade for the above models?