This is why we Co-Drive....
The navigator (right sea) has GasBuddy and Google Earth running on a phone, taplet or laptop. When a good price is found in the area where fuel is likely to be needed or wanted (watch out when changing states), navigator will find a good value station, and then study it from Google Earth and maybe go down to Street View. If it looks promising, we plan that for a stop.
This is all a lot easier to do once the practice is in place and it does save both grief and money.
Matt