Most local tanks have seemed pretty inexpensive to me. Lights and cabinets on the other hand... I really don't have the time to diy, but will before I pay some of those prices ($40 of lumber, $20 of stain and 4 hrs of work saved me $200-$300 in a stand).
(fwiw, I worked in assemply line carpentry as well as construction once upon a time - the work does not scare me, and I enjoy it - just don't always have the time to play and build everything myself).
58 gallon oceanic, Kessel 360 tun sun, pressurized co2, eheim pimp #179 - 2217 and diffuser