Waiz

I finally got a chance to address this post.

You cannot compare the Authentic Nismo kit with the longer nose front bumper and upgraded diffuser, sides, full rear bumper, and spoiler to any replica kit. The NISMO will still carry alot of it's value for years to come, the replica not so much.

Front Bumper with diffuser - $800
Sideskirts - $500
Rear bumper - $800
Spoiler - $900

Paint - Front bumper $300-$400, sides $300, rear $400, install for all three $200 typically what you will pay from a quality shop.
($1,300 at least total)

The rest of the items you were missing, and should also be highlighted because they are important to nerds like me.

-Akebono Brakes Typically $1,800 to $2,000 installed

-350hp engine Would take an install of intakes and exhaust to get close to this level. Currently $1,400 for quality parts of either

-NISMO-tuned dual exhaust with H-pipe configuration

$1,400 to purchase separately with $300 for the H-Pipe

-Nismo branded seats Would have to be custom made ($400+ per seat)

-Nismo floor mats $75

-Nismo Tachometer $700 - $800

-NISMO smooth leather-wrapped steering wheel $300 to get wrapped by an upholsterer

-NISMO smooth leather-wrapped shift knob $150

-NISMO signature red interior stitching $300+ from an upholsterer

-NISMO-tuned suspension with increased spring, dampening and stabilizer rates - $1,000

-NISMO reinforced 3-point front strut tower brace $200

-NISMO front and rear performance body dampers
- $400 each = $800 total

-SynchroRev & VLSD (included) $1,400 for VLSD by itself

--Special Edition RAYS wheels - $3,000

If you had built your car to the level of what the NISMO already includes (like I have tried to do with my Z33) it becomes a better value to just buy the NISMO instead and add a few mods afterwards IMO