Perhaps you should do a bit more research yourself. The $2k for the single setup does not include the turbo, nor does it include injectors maf etc. Now, as far as price goes I will agree that new kits are generally more expensive in a twin setup than for a single. More than anything else is the cost of two brand new head units and perhaps a two into one intercooler. As far as a DIY setup goes...the twin setup is hard to beat. There are an abundance of turbo's with wastegates for the twin setup. There are quite a few more options to be had as well. I'd say generally a twin setup is cheaper to build than a single for your DIY'er. The turbo's are cheaper and usually include working wastegates. The extra cost of plumbing for the twins is minimal. More often than not, your singles will need a quality wastegate wish adds some $$$.