This is the cost of parts I used when rebuilding the 6.9 in the F350(you're not going that far so the gasket set will be cheaper for just the heads).
Gasket set and valley pan (Victor Rienz) $250
ARP head studs $215
Head dowels $12.50
The cost of a used turbo kit will certainly be cheaper than a new one, but plan on adding cost for small stuff that is usually missing from a used setup. I spend around $300 to get a few things that were missing or broken for my used Banks kit.
Also, used isn't always good either. The turbo I have on the crew cab now has a bad seal letting oil leak into the intake. That's means I'll have to rebuild or replace it. I'll likely replace it as (per Russ) they are not a fun rebuild and I really need more air than that turbo can provide anyway with my Moose IP and injectors.
Heath