The seller is bound to furnish all the requisite documents relating to the title of the property before making any sale and the seller asking you for token money, without showing the documents of the property makes the deal suspicious.
So, I would advise you not to give any money upfront to the seller, without seeing the documents and getting them thoroughly scrutinized by an advocate.
Moreover, Supreme Court has held that buying property on GPA does not confer any title on the wire and such sales are invalid. A registered sale deed is a prerequisite for buying any property