I think the confusion is that you're all over the place. Your original budget was $600, then you said it jumped up to $1,000-1,300, how we're at over $1,700.
I gotta ask, what are you doing that needs 2-3 virtual OS's in addition to the host OS?
Learning the distro's...
So you're going to learn how to use a few Linux distros, then what? You're spending nearly $2,000 on computing power to hopefully handle running a few versions of Linux in virtualization at once so you can pick one? Just build a decent PC for around $1,000 then work you way through a couple Linux distros until you find one you like. Once you do, dual boot your favorite plus Windows for gaming. You don't honestly think you're going to be running anything intensive in Linux WHILE gaming in Windows, do you? Seems like a waste.