yeh that is a good point, buying the turbo + install isnt the end of it.
theres the replacement of internal parts, new rods, pistons and so forth. + Tune (probably 5 of these) + New ECU down the track.
+ the servicing cost.
then if anything goes wrong omg.

but nothing is impossible if u want to spend the cash and make the beastiest dc4 go for it.