Looking to buy 1991 1.8 liter turbo miata

I have a chance to buy the following car. It has fairly high miles, but
almost every mod has been done in the last 1 to 2 years, with the engine
and turbo being done this summer, and the car is in great condition, a
couple of dings and small scratches, no accidents. It feels better to
drive than any miata I have driven so far. He has receipts for all of
the parts and 3000 mile oil changes with Mobile 1, and he has done most
of the labor himself. By the looks of the installation, he obviously
knows what he is doing when building a car. So the questions is, what
sort of price range should I offer as a final high offer?

Thanks,

Pat

1991 Mazda Miata (red)
Hard Dog Hardcore Double Diagonal with pad/cover
SSR Competition (Type C) 16x7" lightweight wheels
New Sumitomo HTR+ tires (215/40)

'94 1.8L bottom end (8.8:1 compression) (recent seals, belts)
'99 head & intake manifold (valve job ~10,000 miles ago)
ARP head studs
ACT Extreme clutch
Flyin' Miata/Fidanza lighthweight flywheel
'99 Torsen differential (4.3:1), '00 axles & driveshaft
Flyin' Miata aluminum radiator
Coolant reroute to exit at rear of head
Mazdaspeed motor mounts
Linearized temp gauge, tach modified for quicker response
No AC, no PS

Tec3 ECU with latest software running full sequential
P2-366 laptop & AC power inverter available if desired
Momo steering wheel
5 point harnesses in addition to factory belts
CD player & headrest speakers
Boost (in eyeball vent) & EGT (below stereo) gauges

Garrett ball bearing GT2871R turbo w/ ATP turbo T3 .86 A/R exhaust housing
Tial 40mm external wastegate w/ .4 bar spring
ETD Racing "shorty" turbo header
Custom downpipe by Corky Bell w/ flex sections & wastegate joined in at Cat
Racing Mazda 3" high flow cat, bolt-in
Enthuza Racing 3" single outlet turbo exhaust
18"x8"x3" bar & plate intercooler from Bell Intercoolers
Silicone hose couplings, T-bolt clamps
Vishnu dual feed fuel rail
RC 550cc/min injectors

Racing Beat front & rear swaybars
Racing Beat front swaybar & under engine braces
Flyin' Miata rear suspension brace
Flyin' Miata front shock tower brace & hood prop
Flyin' Miata poly bushings
KYB AGX adjustable shocks
Ground Control coilover sleeve kit
Flyin' Miata stainless steel brake & clutch lines

Top is several years old, window has some scratches that will probably
buff out, no yellowing to the plastic
Front lip spolier

Also Included but not installed
Flyin' Miata blowoff valve
Solenoids for electronic boost control