Should I buy this '01 Audi A4?

[baktash]

Hi everyone. My friend is selling a 2001 Audi A4 quattro awd with 125,000 miles on it. We have come to a deal at $8,500 and I was wondering if I should buy it. The interior and exterior are in excellent condition. He recently rebuilt the engine when he put in the new turbo. Any input before I go through with the deal would be greatly appreciated. Here is a list of modifications:

Suspension
H&R S4 Coilovers
Hotchkis Sway Bars
Perrin Front sway End Links
Rear metal sway end links (oem)
PureMS Front Strut bar
Autospeed DTS
18x8.5 BBS LM Replicas wrapped in 235/40/18 Hankook Ventus V12
18x8 Oettinger RE's wrapped in 225/40/18 Goodyear F1 GS-D3s
Lifetime Alignment from Firestone

Audio
Alpine 550w sub amp
12" soundsplinter rlp in sealed box
Eclipse 4x75w 4ch amp
MBQuart Component reference front speakers 5.25"
MBQuart Discus 5.25" rear speakers

Engine
APR 2.5" Exhaust
E-code 2.5" Test Pipe
Wayne Angle Block eliminating CEL for test pipe
M-factory catch can
Custom made 3" intake piping w/Apex'i Filter
Neuspeed Xtreme inlet pipe w/larger adapter for GTRS
00Black18t's Heatshield
ATP GTRS Eliminator Turbo
GIAC tuning
440cc green giants injectors
Phenolic intake manifold spacer (Powergasket Plus)
Racetec FMIC
NGK BKR8EIX Iridium spark plugs gapped @.028"
ATP Exhaust Manifold
RS4 Motor mounts
PureMS Snub Mount
Hallmann Pro MBC
Stratmosphere Hyperboost HX DV
Southbend Stage 4 OFE Clutch w/SS Plate with new stock flywheel

Brakes
Porsche Boxster 4pot calipers/ A8 312mm rotors / OEM Porsche Pads in the front
Axxis ultimate pads in the rear

Exterior
Rieger RS4 Front Bumper w/Deutschland license plate
S4 Side skirts
S4 rear valence
6000k HIDs
Clear-corner modification

Interior
VDO Boost gauge in center vent
V&S Short shifter
Custom black shifter surrounding
Euro Blind Spot mirrors