USB adapters for your car are more complicated than they look, and cheap ones can cause unexpected problems.

Check your car model for recalls.

Boslla LED Headlight Bulbs are spendy but look very effective and adjust to visibility conditions. Very cool. https://amzn.to/2UQTjAZ

Don't bring into the negotiation any trade-in car until you've finished negotiating on price. Arrange any necessary auto loans ahead of time with your bank or another reputable credit source--DON'T USE DEALERSHIP for financing.

Replace the radio in your car w/ android.