A film set at Beaconsfield Studios was used for the scenes in the town centre: where Troon has to stop for the old lady (Esma Cannon) on the zebra crossing, where Freddie Fox's boss (Dick Emery) tells him he must sell more cars or he will lose his job, where Troon and Chingford get caught up in a traffic jam caused by a broken-down car, and where the driving test centre and the County Bank are situated.
It turns out that Murdoch Troon was quite "canny" buying the old Bentley Red Label 3.0 litre. Today that car will be worth over a quarter of a million pounds sterling, and easily over a million if it had been at Le Mans as claimed throughout the film.
The scenes outside Mrs Staggers Lodging House were filmed on the Pinewood Green housing estate, Iver Heath, Buckinghamshire. Close to Pinewood Studios it was also used in Carry on at Your Convenience (1971), Carry on Cabby (1963), and Les Cinglés du camping (1969).
The final scenes, where Troon, Chingford and the police chase the robbers onto the motorway where they crash and overturn their getaway car, was filmed on the M4 motorway (near Junction 7, the Huntercombe Spur) which was being constructed at the time so was not yet open to traffic.
Three cars - the large American car that Freddie's first girlfriend drives, Freddie's green Bentley ("The Fast Lady"), and the red sports car that Freddie's second girlfriend drives - all have their real white-on-black number plates covered up by the same white-on-red trade plates with the registration "616 H". Trade plates are used by the motor trade when driving vehicles which are untaxed, and the implication is that Freddie has been "borrowing" the cars and the trade plates from the garage where he works.