What is the safest way to accept payment, selling car as private sale from private house.

May sell in auto trader or local evening paper.

I ask this question because we sold my sons tv through a private add in the paper a man came and gave us some "FORGED" money.

We are on our guard this time, would a bankers draft or B/Soc cheque be the safest.

If it has to be cash should we check every note with a pen, extreme measures but there are a lot of "bad" people out there!