When should I get my turbo?

yep I ran into some 'interesting' money problems so I haven't been able to do a single thing to my car except buy a steering wheel, I'm the man

ok, so to start with, uprate the fuel pump, regulator, injectors, fuel rail? (maybe later), then get the turbo and leave block alone for a while (til i can afford it) and set the turbo at 4 or 5 psi? Would you recommend getting the fuel management system (think i'm gonna go with hondata) at the same time as the turbo? And I know a turbo needs a nice free flowing exhaust but I wouldn't do any damage using it with my stock exhaust for a while would I?