If it were my project, I'd start with a budget, then list and prioritize every little thing that needs to be done and an approximate cost.
I think for a studio, especially in a basement, getting good lighting is your most important need. (That is assuming the space is warm and dry, if not, those would be first.) So my list of priorities would be something like this:
Walls (repair, paint) and trim
Work space (tables, easel)
Draw out what you want the space to look like, where your tables and shelving will go. That way you'll know what size pieces to be on the lookout for. You can probably get tables and bookcases for very little. If you buy new, Ikea has great tables. Our work table now was my college desk (umm...like 20 yrs ago), I just cut the legs down. For craft supply and sewing storage, I have a tall Ikea bookcase. The kids stuff is on the bottom, and mine is on the top. I use tons of baskets to sort everything. My yarns are in drawers in an antique chest of drawers.