+7 billion for northshore for quality cars
as for the mirror rust, i have never seen an M35 with mirror rust, it appears to be an unfortunate problem for C34 owners.
M35 owners should watch out for turbo death, but this is not ALL of them. Mine is still going fine at almost 130k on the clock. i guess it comes down to how well it was looked after in japan. phycially sighting the car will determine how well it was treated. budget around the 2-3k for rebuild and installation. probably more depending on the turbo you go for. its a bitch of a job, but not impossible.
as mentioned, servicing is cheap and easy. i do oil changed in my driveway with a small ramp. piss easy.
a fantastic upgrade is a valve body for the transmission, makes it shift gears more swiftly than the stock programming.
rego is simple, insurance MAY be more difficult. id reccomend shannons - assuming you have a garage. if not, then just cars may be your best option. there is an insurance thread with all this information.