Message to self: read all of a Post before hitting Reply Button.
$12,000 USD is asking an awful lot. Good luck.
Plus the maximum payload for the Mav is 1,200 - 1,500 lbs, depending on Model. Payload includes anything in the Bed + Passengers + Gear. So you can only add 600 lbs including...
let's be honest the Mav's seats are not the most comfortable. I have the fake cloth seats (made from some polymer). If I had the fake leather ones my underwear would stick in places I never knew existed.
Think carefully about your decision. What made you buy the 23 Taco when the Maverick was also available? The Taco is a mid-size truck. The Mav is certainly a compact truck.
If you want to tow, the non-4K Mav has a towing capacity of 2,000 lbs. With the 4K Tow Package, well, 4,000 lbs. 4K...
I read on my news-feed the other day that Rivian ranked bottom of electric vehicle manufactures in terms of reliability, recalls, etc.
Do your research.
Engine block heaters used to be standard equipment on Canadian Mavs. As I live in Vancouver (and park my Mav in my garage), I have no need for one despite the recall.