I'm thinking about buying a 2006 g35 Infiniti but it
needs a cooling fan assembly iOS it worth me
Any car can be worth buying if the price is right. The real question is, can you do the work yourself or pay someone to do it and still make the car an attractive buy? And, is that the ONLY problem with it? Sometimes one problem can mask a host of additional problems.
Not enough information to say. Don't take the owners word that this is the only thing it needs!