The problem with my stash is that it's all small pieces. I used to work for the LQS, so got very very good discounts. I was just starting quilting, so I'd pick up random pieces that caught my eye: almost always remnants/leftovers/qtr (not FQ) yds. Now that I am quilting for income (well, trying at any rate), I find these small pieces to be a hassle, but I just can't bear to give them up! On the flip side, because they're mostly small pieces, 90% of my stash fits on 3 30x12 shelves... (not 3 units, 3 shelves total)
I'd wait til you move into your new quilting space before you buy anything for your stash. And then, especially if you're a planner, I'd only buy blenders for now. Nothing smaller than a 1 yd piece, unless you pick up FQ packs (those are far more useful if you plan to do block swaps, though)