Maintenance-wise should be same as the engine (except turbo) & drivetrain are basically of the same specs. For reference, my previous evo4 (bought when mileage was 60K and sold at 160K - used for 3 years) incurred the following repair jobs :
ignition coil - RM1300++
water pump - RM800++
starter motor - recond - RM300++
leaking head gasket - sold off before repair
(prices not inclusive of labour)
All these are on top of the regular maintenance. General rule, for higher mileage evos, chances of incurring repair bills on wear and tear items are higher.