The guys I was familiar with carried a shotgun in the front seat and a mini-14 in the trunk.
So, 2 shotguns.
I knew a deputy about 15 yrs. ago who’s department was dirt poor cash wise. He carried a Ruger P89 as his sidearm but they didn’t issue long guns unless you wanted to pony up for the piece yourself. He had just started and had little funds but he did put a rifle in his trunk, an old Russian Mosin-Nagant and some stripper clips. As he said it was better than nothing and he was pretty good shooting that thing.