Hi there,
Most common issues are VVT rattle so I'd look for it to have been changed if the car is over 80k miles or factor in the cost of replacement during your ownership. Factory turbo oil seals fail a lot on these cars so listen for funny noises when the turbo spools or excessive smoke at idle once the car has warmed up and sits for a bit.
I've seen the fuel tank baffles come loose in a good few mk2 3MPS's now which presents an annoying scraping noise when driving but other than that just your usual service history checks and rust underneath. A few older cars have a boot full of water due to water ingress through boot or tail light seals or from the spoiler fixings so check that also.
If modded you will want to know where the car was tuned and that it also has uprated HPFP internals fitted.
Think that's it!
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2010 MPS3 Mk2 Forged / Sleeved Engine, CS Cams and Crower Valve Springs, BNR S4 Turbo, HTP 3.5" Intake, HPFP Internals, 2050psi Fuel Rail Relief Valve, JMF Intake Manifold, DNP Exhaust Manifold, Dual OCC Setup, Cobb Turbo Back Exhaust, Airtec FMIC, Port Methanol Injection ..... Tuning in progress with a goal of 480-500bhp :-)
