Alphabet leasing conditions

Hello together, I am entitled to a company car above my employer. Leasing partner is alphabet and I have the choice between Audi, BMW and VW. I noticed that the monthly leasing rates (full service leasing) differ very much. Just for comparison (basic equipment without extras): Audi A4 2.0 s-tronic > 1000€ BMW 320D Touring Automatic: approx.600€ VW Passat 2.0 DSG Highline: > 1000€ What is the reason that BMW is so cheap and Audi/VW so extremely expensive? n Leasing conditions or the alphabet belongs to the BMW Group and offers better prices?