Cheapest way to do the front is cut the springs. I'm reasonably confident the flipping of the leafs won't work because I can't forsee the hangers being low enough to do it.
Cheaper isn't always better.. I don't recommend cutting coils I did mine about 15 years ago.. Drove it for 2 weeks until my belltech springs got here. It sucks! You can block the rear for about $30 bucks or less on Craigslist or Kijiji depending where you are, get a set of lowering blocks and u-bolts. Heck the kits only run about $80 brand new. Spindles are more than coils, but it also depends on the drop you want... 3" springs and 3" blocks (remove your helper leaf for another 1" drop) will run you around $250-300... which is probably the best bang for your buck.