Here you will find an explanation of the necessary documents to purchase a vehicle in Spain. Green links show VALID documents, red links INVALID documents and orange links VALID documents with expiry dates.
You will need a copy of your residencia (green A4 sheet) or new small green residencia (id card size) and also a copy of your passport in date, if your address is not correct on your residencia then this is all you will need, if not the you will also need a empadronamiento “padron” (wich is a register in you local town hall) or a copy of the deeds.
You will need a copy of your NIE number (tax identification number in spain) in date and also a copy of your passport in date. And again if your address on your NIE number is not correct we will need a empadronamiento or copy of your deeds.
As from 2013 old yellow NIE form and old white NIE form are no longer valid.
Please note that all new NIE numbers have in the bottom right hand corner a 3 month expiry date from day of issue of the nie number, if this is your case and 3 months have past then you will have to get an up to date print off of your NIE number to be able to finalize the transfer of the ownership. See example.