The most adorable tiny VW Bus was featured on Call of the Small a long time ago. I search eBay every once in awhile to see if I can find one for my own collection. Searching eBay is dangerous, because there are a lot of cute wee automobiles. This 1:87 scale Scirocco by BUB from nathan1002010 caught my eye.
In a 1:12 scale dollhouse, this would be slightly smaller than 1:6 scale, so a playscale car for a dollhouse. Look at that tiny VW emblem. :O
Race ya! :D