Smoke Nitride finish-$450. It's a proprietary finish involving melonite, then cerakoting, than hand buffering the finish.
According to colt custom shop-
Enhanced series 70 reliability package-245
Serate front strap-185
Serate msh- 185
Carry Bevel dehorn-135 (cheap most Smith's charge 150 or more)
Flush crown - 95
Fit and blend grip safety(independent of a custom part price)- 260 (evolution armory- colt doesn't list blended grip safety price)
National Match trigger tune-250-same at evo
Match fit barrel bushing-$150-not including price of a nighthawk bushing.
Custom rear sight-colt does fixed Novak's for 120
Gold bead front sight-colt doesn't offer but others offer for-150
Custom hammer-no idea-
High cut trigger guard-175
That amalgamation of prices comes out to 2725.
I am not certain on the cost of the finish at 450 as I am only going off what I have seen posted
Also, colts custom shop is fairly cheap compared to most Smith's out there.
If it's not your cup of tea, fine. But don't say it's less than $1000 worth of work.