One thing I haven't seen mentioned, is the barter value of surplus ammo. Now of course you'd keep what you need as much as you need, sell, trade for food, medical items, water. Security measures would be needed for high risk contact with others . But ex. Ammo would be VERY valuable.
And as far as roads being blocked, you cleary need something that will go off road,, I picked up jeep cherokee ZJ not long ago and with a few mods and 31inch MT tires these older rigs are Very capable ( 6-8 cylinders kick ass) and really cheap nowa days, 2500truck+1500 mods you got yourself a capable bug out vehicle. Carry gear and gas, spare, on a roof rack, tons of room for gear in back.