If you have an Android and a car that is compatible with Android Auto, then it will not cost you anything to install Android Auto into your vehicle. However, if you have an older model of car then it might be not compatible but you can purchase an aftermarket radio to be installed into your car that will be compatible with Android Auto or Apple CarPlay.
Some good brands for these sorts of radios are Sony and Pioneer and could cost you anywhere between $100 to $500 to buy from a retailer. If you’re knowledgeable with installing tech like this into a vehicle, then you should be able to install it yourself free of charge, however, if you’re not clued up on this area then we’d recommend hiring a professional or taking it to a garage for someone else to install. The total cost of installing the new radio - including parts, could be anywhere between $200 to over $600 depending on where you go. Older car models may require more time to be spent trying to install as they may not have the correct or up-to-date wiring as new models, therefore the cost will be larger.