<prompt> Human: First off, I am a delivery driver using my own vehicle, a 2011 Dodge avenger express. Its rated for 21 mpg city, but the way I drive it Ive calculated it at about 18-19 mpg. I am currently spending 400month in gas and am considering a more fuel efficient car because I would really like to get my overall costs down. One important note is that I owe 4800 on my avenger loan still, and I pay 165 a month on it. so Im underwater quite a bit there considering its only worth about 2500.I am considering a 2018 Nissan leaf. After running the numberscredit, I would owe roughly 570 a month for a payment after rolling my current loan into the new one, but only spend 40-60 in fuel home electric billI am also considering a used Prius. I can get a decent one for about 10k before rolling my old loan into it, so really its 15k. The monthly payment would be about 260month and fuel costs about 150-175month.Just curious to hear what you guys think is my best financial option would be. Im pretty terrible at figuring this all out and figured you guys would be the best people to get advice on this from. Should I keep the Avenger until its paid off and just eat the gas cost? Or should I focus on fuel efficiency and east the extra monthly payment? I do worry that gas will only get more expensive from here. It already is.Thanks Reddit!  <response>: Unless oil goes to 200 barrel and stays there for years it almost never pays to buy a new vehicle for gas efficiency.Just keep it 