We are getting our house ready to put on the market. The only problem on the horizon is our neighbours. The house is rented by 5-6 Eastern European people in their mid to late 20's. They are nice enough, quiet, hard working - they never have parties and keep the house in relatively good condition BUT they smoke weed in their car in the driveway.
They obviously smoke in the car to keep the smell out of the house but the smell is really strong. They don't do it constantly but I'm worried incase they light up just before a viewing 
I don't know how to approach it, should I say something ? We don't know them very well and their English isn't great but I don't want this jeopardizing the sale.
All advice welcomed!