No i haven't i dont even know what to look for in parts, that's why i would like something built already.
They sell kits! They have all the parts needed, Ahren is a member here as well. But if it was already built, turnkey, it wouldn't be DIY then, and at the size you want it would probably be about two to three times your budget for a turnkey system.
Depends on what you're doing. For light work it might be fine. But there was another person here who bought a similar machine and was having problems. The unsupported rails, single bearing blocks, smallish gantry risers all add up to a machine that will flex under load, unless you're taking very very light cuts... and that gets old pretty fast!
If $3000 is your absolute ceiling, I think you need to look into kits. I'm not sure if FLA is better with their customer service/delivery time, but the FLA-100 is probably perfect for you. I'd also look into contacting CNCRouterParts. Maybe they'd be willing to do a smaller kit for you.