Sorta off topic, But I once went to buy an exhaust for my 318is... Met the guy at a petrol station, Got talking and had a look around his car (Boston Green 318is) and randomly managed to buy it for stupidly cheap, That was a good day!
Wish I never sold it though.

Anyway, maybe write down on a piece of paper that it's a nice car and you'd be interested in buying it if it was for sale and your contact details and stick it in the letter-box?