The father of the couple that service my car (father and son team) used to service Yorks. Now they service my car but not at the box change level.
For instance one problem at the main dealer was 'diagnosed' as requiring a new hydraulic pump at £1000 plus labour (VAT may well have been extra). They fixed the pump with a new washer at a total cost of £18.
You might save a bomb on training and 2nd/3rd line maintenance but probably spend a fortune on 4th line.