I thought it could never happen to me....

[5potTurbo]

Wow!
OP: I think you were very, very fortunate with this one.
I am surprised that HPI didn't have the records of the original (correct) VIN as stolen.

[va1o]

Could it have been stolen from abroad?

I guess you don't know the VRM it had originally, only the VIN.

[The Wookie]

buzzer said:

Nice theory, but the Z3 was not affected by Nikasil so I believe

Quite possible, I just assumed it was any bimmer with the M52 engine

[Sonic]

Christ, what a nightmare. Very lucky you found that OP, and very decent of the seller to give you a full refund. Just goes to show...

[Jonny_693]

So could it ever be put back on the road leagally then? What happens to ringed cars?