Bought a store house! 4 bed 1 bath

So it needs a lot of work still... Sheet rock, insulation, blinds/ curtains ( what is better and why?), vinyl flooring upstairs, whole kitchen, new vinyl Windows  needs.to be put in. 
Already has. Forced hot air heating, plumbing and new electric wires placed in by professional electrician. Has public water and sewer. Tile floors on first floor. 

Any ideas on where to get supplies cheap? We have looked on Craigslist, Facebook marketplace, and the restore's around us. Any other places we have missed?
Located in Maine.