anyone out there do annodizing?

[t-maxxracer32]

hey guys soon i will be ordering a bunch of aluminum parts and it would be sweet for them to be all black aluminum.

couple questions.

-can you annodize any color to black? (for example... chrome to black? purple to black?)
-if the item is used will it be ok? (aarms have usual wear and tear)
-how expensive is it?
-does this stuff last?

if anyone here can do it or knows someone who can let me know!