I was going to build my tank myself untill I found someone who will build it for less than I can purchase the glass for. O phoned a number of glass companies here and got a wide range of pricing but all were way too much.
Go to your lfs's and get a few of them to quote it, same with glass suppliers - that will tell you if it is worth it. I found a lfs that a a guy that builds tanks for them that isnt trting to retire eaqrly buy charge an arm and a leg for a tank
Good Luck