its not too bad, I'm in the process of doing the same thing, in total it cost me around $500, a MIM tele is like $450-500, but seriously, they suck. And plus, i have 2-pc swamp ash body, fender brass-saddle bridge, fender vintage noiseless pups, licensed maple neck, and etc (nearly all geniune parts, or very closely matched). And i also did the body in nitro with a yellowish-tint.
the money u save on cost isn't bad, but the main idea is that you're building it to your ideal specifications and preference.