One of the best possibilities for long term survival on a budget may be a simple old RV setup in a very isolated farm area, the farther back in the hills the better.
The reason I say this, it has a lot going for it because it is already a self-contained system that runs on Propane and 12-volt DC batteries. When combined with solar power or wind generation which is made to charge 12 VDC batteries and a propane system that can be connected to a large tank, the possibilities of a comfortable existence becomes possible. Yes, they do have their downsides as well like bad insulation and a weak roof, but those can be overcome easily.
The property, farm or partnered farm to park the RV on.
The first thing is you must have a property to do this on, so go to my "farm Property" page and learn how you can buy a piece of farm property very economically, and what you should look for in that purchase.
The RV (Trailer, conventional or 5th wheel)
This is a personal choice and of course cost factor, but here are some thoughts. You must purchase a 4-season trailer because they have better insulation and windows in them. Look at the battery holding area, can you add more batteries to this area, if so good. Does it have an external propane jack on it for a grill, if yes, perfect (can connect your big propane tank to it). Does it have an Onan propane Genset built into it, if so Yea! How big are the holding tanks? what’s the roof look like? Is it big enough for your family to live in? Does everything work? Is it a toy hauler with built in gas tanks, if so good!
I have looked myself and found many large older toy hauling trailers with generators selling for less than 10,000. Who cares what brakes, tires, even the roof to some extent if you can get it to the farm and setup without issue. BTW, you can find many people with trucks to haul it up there for you.
I look for toy hauler models, because they are huge, have a built-in shop area and huge storage potential.
The RV in a Pole barn or Quonset
hut for long term survival
The Pole barn or Quonset hut
Due to the weakness of the roof on RV's and to have a good work area, getting a pole barn setup to place the RV in is a must have item. Not only does it protect the RV from weather, it will be a platform for a Rain Gutter water catch system, platform for Solar power on roof area, possible protection from EMP with steel roof and great work space outside the trailer itself covered. You can start with just the pole barn and roof only and add sides and sliding doors later. Same is true for the pad and make sure you get a good pour on the pad. Later you can add a cellar or storm unit to it without issue.
Large underground Propane tanks
500 gallon to 1000 gallon or larger tanks. If you are not aware, the refrigerator in a RV trailer uses a tiny amount of propane and a tiny amount of 12VDC. Even a 7-gallon tank (on most RV's) would last months. So how long would a 1000-gallon tank last? Now you’re getting the picture. Plus, this gives you a gas stove and oven, hot water tank to take showers in. Oh yes, a little comfort and if solar/wind needs a boost, you could kick in the genset occasionally. A 1000-gallon tank would run you about 3-4000 installed and it would last a long time.
Septic tank system for trailer
A typical small system would run you about 3-4000. If you had good drainage away from streams or ponds you could build yourself a system less than that, that would work just fine, including a simple "shit pond" to drain it to. (make sure it is downwind from pole barn)
Rain gutter water collection system
Rain barrels and gutter system is a must especially if you have no other water means. If you do not have a spring, pond or creek to draw water from, you are going to need as many barrels as you can get. It easy to move and filter water to your RV by a simple RV water pump attached to a hose from barrel. A good ceramic or paper filter system will run you about 150 dollars. Again, run by your 12VDC system. If you do have your pad near the water source, use that same pump to fill barrels or trailer by solar power. This would also help water a garden as well during dry conditions.
Wood stove for heating
When the propane finally runs out, you are going to have to stay warm. Having a large wood stove in the shop area along with good chimney system is going to be a must to keep everything warm. Not only that but also think about cooking as well. Having a brick/stone fire oven and hurricane wood stove with chimney is also a good plan to save on fuel.
Toy hauler advantage
Instant garage, how can I state it any better. A great location to store tools and equipment in a shop area for you. Plus, it normally has additional sleeping areas above it and possible a half bath on some models.