$800 for a 3ft tank? That seems way too high... you can get a brand new ready-made standard glass 3ft tank (90x45x45) for around $80-$90, or a high clarity low-iron crystal glass version for around $160-$180. Just check at places like Seaview or Rainbow Aquarium.
If you are getting tanks with standard dimensions then it'll be easier (and usually cheaper) to just get from LFS, unless you are looking to get a tank with special or odd dimensions, then no choice have to custom make.
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