My Biggest challenge to staying out longer in a van or RV 

This is a great video on several levels. I'm currently designing my "last" adventure rig, which will be a pop-up slide-in camper on my F250 4x4 truck. Listening to videos like yours is helping me to sharpen my list of gear & preparation needs. For me: Smaller is better... less is more... slow is fast. Living with minimalism and deep joy requires thought and experience. Thanks for sharing!

We carry extra water but in reused gallon bottles--it also is more convenient to transfer water to 1 gallons from our 5 gallons. We have a water tank for the sink. Find a way to fill your tank by hand (without a hose and pressure). That will give more options to fill up where you can't use a spigot. Many parks and visitor centers have water but don't allow you to hook up a hose. In Mexico we used water purification back before we had filters. No harm in taking a backpack filter kit for emergencies. You can say you don't expect to find water, but it would be disappointing to have water that you can't drink if you do find it.

I got out with six 3.5 gallon water jugs that I use for drinking, cooking, and showering which will last about 14-16 days depending on how often I shower. Like some of the other commenters, my stomach gets upset when drinking plain water - though it's not as bad if the water is cold. To help keep the stomach issue at bay, soaking a tea bag in a 20 oz bottle of water can provide many different flavors. Also, I sometimes soak small chunks of (dried) apricot in a water bottle, which tastes really good and satisfies my craving for something sweet.

I totally understand your water situation. But it varies by location and time of year. I live in Montana and I often visit forest service campgrounds in the fringe seasons. In the summer, many of them have water available, but not in the winter. I often make these trips solo. So I carry only a 4 gallon jug. I will pick up gallon size bottled water every few days from convenience stores. I can usually get by for several days on my 4 gallon supply. A big problem I get faced with is the accumulation of trash! It gets hard to find places to dispose of trash when those campgrounds don’t have trash collection. I often spend time in some areas where even the closest small town doesn’t have available trash dumpsters. My other limiting factor during summer, when I use my RV trailer, is holding tank capacity. Yes, I have a portable tank, but then there is the challenge transporting it to a dump station. So my limitations are a mixed bag depending on whether I’m out solo in the fringe seasons or camping with my wife in our trailer. My list would be: Storage tank capacity Trash accumulation Water.

I've never boondocked in the same spot for more than three days but hopefully that will change after I retire. The collapsible water bags are a good suggestion. It's funny that you are defensive about using the small water bottles. I use them without guilt but I do refill when possible. I joke that filtering water is one of my hobbies.

Yes, my immediate thought after reading the title was water. The thing about filtering water from nature is that it's often so silty that it blocks your filter & then you can't filter anything. There is a solution though. If you boil the dirty water, this destroyers the chemicals that keep the silt in suspension. Then you let the boiled water stand overnight & the silt will settle to the bottom. It is important to not move or tilt the container as this will stir up the silt again. Instead, siphon off the top clean water into a clean container, then run the siphoned water through your biological filter. For filtering, I use a Sawyer 2 bag gravity filter system. It's a system I can use for solo hiking, or I can use it for the camper trailer if it's 60 liter tank ever ran dry. Of course, this assumes you can get water from the environment you are in. As you say, that's not always possible, but you can replenish your supply when it is. Oh and if there is a lot of organic material in the natural water source, you may need to use a cloth filter, anything you have is better than nothing.

My biggest challenge is when my van breaks down in the middle of nowhere

Why don't you have some gallon-size water bottles instead?

Well….I hate to admit it but I don’t drink water and only drink Pepsi zero. If I’m doing something in the summer that’s got me sweating and hot I will drink a glass of water but that’s about it. We have a 30 gallon stainless steel water tank in our van but it is only used for showers and cooking. I tried only water a couple times but for some reason it gives me a gut ache and horrible heartburn ?? We use ice in a yeti cooler so probably 5 days would be our limit on how long we could stay out in the summer but winter I’m thinking we would be good for probably a month.

The answer to not running out of water is bringing more water. This can be applied to so many things. I avoid being broke by just bringing more money.