Why the cüzdan"ı" here?
his - wallet
cüzdan-ım - my wallet
cüzdan-ın - your wallet
cüzdan-ı - his wallet
Why not yaşlı?
"yaşlı" is the opposite of young (and therefore is normally used with people). "eski" is the opposite of new (and therefore is used with normally with objects, but can mean "former" when used with people).
why not cüzdanisi?