Would also like to see what others have done! Seems like most of them i see are super spendy for what they are..
I may go look on ebay and amazon to see what they got, monitors seem super cheap..
EDIT: Found this one on amazon
HERE Pyle has been around for a long time and seem decent, and not too bad on the price, would want to get another cable though and do a discount at the hitch/tongue and probably just mount it on the bottom of the trailer, Would probably spend more time fishing and getting the cable in the truck than any other part, put that on my wishlist for now
Found another one from Pyle that looks nice:
HERE