Trying at a dealer, buying at another?

Hello, I’m a bit in a mess. I want to buy a Golf GTE, but the dealer on site has no such as a demonstration car and the next dealer who would have one is about 40km away. Actually, it would be perfect to test the GTE there and then order it from the dealer on site. However, I find that quite unfair, so the second possibility would be to order the GTE at the dealer’s where I also test drive. Only then could the dealer on site My family has been buying their VWs there for decades. So how to proceed?