Anyone can baton a knife, split some 1" limbs or saplings, use a stone to drive 3" nails thru the wood. If you stop to turn around or remove the (dozens) of branches, or to turn around, your vehicle will get shot up. If you drive on thru them, you won't be going far on 4 flat tires. How much of your vehicle load can you carry on foot, hmm? :-)
A mountain bike, with solid tires, can be floated on your pack-poncho-raft, swiminng behind it. It can be simply lifted over fences. It is easily hidden in a little gully or some brush. In a pinch, it can be sunk in the mud and water, or roped up into a brushy tree and camoed there. You can walk along side of it, in really bad terrain and at least, not have to carry the weight of the gear and food.
So your little circle of buried drums of goodies can be 30 miles or so away,and still be reached the first night of shtf. Very few people live further than that from woods and water. Once you get below ground, and come out only at night, leave no tracks, have almost no food in the shelter, show no light, don't cook, and make no noise, it is extremely unlikely that anyone will know of your presence. Have a Kindle full of "how to" info to keep you occupied, and a solar charger to keep it functional.
Avoid everyone for a year, and let the diseases, fire, starvation and fighting kill off nearly everyone. Diesel fuel will be everywhere, and diesel vehicles and generators will run on peanut oil. Stuff will be laying everywhere, waiting for you to use it. The animals will all be eaten, as will the freshwater and seashore fish, and most of the edible plants. So you need sprouting seeds, non hybrid seeds, and half a drum full of paraffin ($1 a lb on the net) for a year's cooking. it sends up almost no smoke, scent or flame, can boil a gallon of water in a very few minutes. You will, however, have to use the big "can candle" in an open to the sky pit or gully, because of the danger of O2 and carbon monoxide in confined area. Best to do your cooking a ways from your dugout shelter, because the scent will draw dogs. Best also have a suppressed .22 auto rifle or pistol, with subsonic ammo, and at least active and passive Ir capability, so that you can brain them in the dark.
The next night after you arrive at one of your spiderholes, best get busy expanding it into a narrow, shallow, dugout shelter, with not much 'overburden" of dirt, just sod and a few inches of dirt for the sod roots. If you can't get the right sort of dirt (damp clay) needed to avoid having to shore up the roof, best have buried some shoring materials. ASAP, dig a short tunnel, so that you can come up behind anyone one anything that is messing with your main trap door. a couple of moustraps, rigged to fire a .22lr rd in a short pc of pipe, will wake you if anyone raises a lid. the noise will also scare the hell out of the intruder, "buying" you a few seconds to get to the other end of your place, and perhaps be able to quietly shoot them all in the back, before they can enter and do you harm.