Just a few comments reading this!
First you don't need to rip off ,deceive, or act like a bandit (like Dick Turpin the Highwayman) to make a reasonable profit selling sales & service on vehicles like MB Sprinters.
If the narrative is true, then its a damming indictment of this dealership, or any provider for that matter .
Frankly the BBB has lost it effectiveness in the modern era of social media.
It has always had its limitation anyway, and really focuses on small business trying to make a startup headway in the commercial world.
They won't take on complaints about big business ,nor banks, financial institutions nor insurance companies & the ilk's.
These organizations have bevies of deep pockets & attorneys to crush customer objections & negate any meaningful complaint, so it a waste of time.
Coming from this auto business, you can only do so much, but the most effective method is to politely write a recorded delivery letter to the dealer general manager and the (in this case) MB customer relations.
Now I can't state that this work with the right positive reaction.
I can cite however, an incidence where one Landrover Denver Metro dealer ripped us off over devious parts & core exchange tariffs. In spite of us doing some considerable business with them over 15 years AND providing written invoice proof of double dip charging on parts etc to the management .
This was to no avail in our case the whole thing fell silent.
Landrover USA you got an "F" , including an "eff ouwf mate"!
So take your business elsewhere.
In the case of Landrover and their appalling dealership support in the Denver Metro, I source capture parts from a Salt lake City dealership.
Prices are at least 40% less, and delivery response times about 30% better even with UPS involved .
Remembering the all time best quotation as an ex Landover B/L employee .
Not everyone can own Landrover, We are trying to maintain the intrinsic exclusivity of the marque!
(Dennis' comment what a lot of Brit bollocks)
So its buyer beware (Caveat Emptor) in all things as consumer not just "motors".
Dennis