I would at the very least get a VAFC to tune the fuel curve. I'm in the process of building my own kit also, its all about frugal shopping. For building a cheap turbo kit, ebay is your friend. I picked up a saab t3 for 45. Got a rebuild kit for 40, its soaking in parts cleaner now for about the last 6 months, I just havent had the time to put it back together, but it should be really clean by now. You can pick up sparco type Front mount intercoolers off ebay for under 200, If you have a CAI, it can be used to plumb from the intercooler to the TB, just have a BOV flange welded on it. You can find places that do custom manifolds for under 400. I've seen places that will sell them for about 2-3, You can always pick up BOV's and Wastegates off ebay for cheap if you look for a long time and pick up when noone seems to be bidding. Same with a VAFC. I also plan to get a set of 450 injectors and go with a vafc hack to regulate fuel. The tubing, and downpipe can be done at a local muffler shop, You can pick up the downpipe flange for the turbo for like $15 online.