Building a 9.9 sec Evo can cost you $15,000-$40,000 depending on how deep your pockets are and how crazy you want to get with the build.

Different parts compliment each other and help performance. Some parts you need, some you don't. Some mods are more for "insurance" like stage 5 axles or built transfer case. You don't need them, but they are nice to have. You don't need a carbon fiber drive shaft either, but it sure is nice to have. Etc....