Has to be four seater?
http://www.autotrader.co.uk/classified/advert/201041370559189/sort/priceasc/usedcars/price-from/40000/body-type/saloon/fuel-type/petrol/maximum-mileage/up_to_20000_miles/price-to/50000/engine-size-cars/5lplus/make/bmw/radius/1501/page/1/postcode/dd68hg?logcode=p
you could always de-badge
http://www.autotrader.co.uk/classified/advert/201040369995369/sort/priceasc/usedcars/maximum-mileage/up_to_20000_miles/maximum-age/up_to_2_years_old/engine-size-cars/5lplus/price-from/40000/price-to/50000/make/lexus/page/1/radius/1500/postcode/dd68hg?logcode=p