I would love any advice folks may have either about specifics (use these solar panels not those) or general (living in an airstream will make you hate XXXX). Thanks!
Since airstreams are shiny and curved, flat rigid solar panels are probably not going to be what you want. There are a number of thin film panels, and although most of them are less area-efficient than commodity silicon PV panels, you can compact them more easily and then deploy once parked. Thin films can easily win on weight-efficiency too.
PV's are unfortunately, regardless of efficiency, not going to absorb enough sunlight to do much more than charge your laptop and maybe keep your batteries topped off and run a fan or minifridge. That is, unless, you have a ridiculously large number of PV modules taking up half your interior space, or you only camp in spots that are nice all year.
Living requires heating/cooling, food, water, toilet, and bath/shower. Those are usually the hardest things to get right. Active climate control requires wall or truck power, or a genset (yuck!).
Lastly, budget a lot for an airstream, and budget a lot of time and money for the renovations you want to do. People in the know may tut-tut the upgrades you want to do because they are purists when it comes to airstreams.
Passive solar approaches to keeping things a bearable temperature will drastically reduce your energy dependence.
You need toilet facilities. If you are healthy and have clean habits, you do not necessarily need to shower every single day. Carry hand sanitizer and use it liberally. If your hands are kept clean, everything you touch will stay cleaner.
A super short haircut can also help you stay adequately clean and decent-looking when reliable bathing facilities are hard to come by.
You can live without a mini fridge. It isn't an absolute necessity. It does require some lifestyle modifications. Only buy milk or other fresh items when you are about to use them. Get hot meals at eateries or cook with mostly shelf stable goods. You can also use a seed pot for preserving food without electricity. It isn't as good as a fridge, but it may be an option that works well for you to have some options while freeing up electrical load.
If it gets fairly cool at night, assuming you aren't in bear country, some things can be stored outside overnight to keep them cool. I have become quite fond of sodas cooled this way instead of being served over ice.
My experience: Cardboard, paper, cloth items and upholstery generate heat, much like a compost heap does. Limit those items and keeping your place cool in summer is much less challenging. You can reduce that amount of cardboard in your space by removing cardboard boxes from food (crackers, snacks, etc) and trashing them the minute you get groceries home.
http://bootstrappedweb.com/80-brecht-palombo-on-longterm-tra...
A typical RV park (or many of the campgrounds in Oregon) will have sewer and electricity hookups for RVs. That takes care of your two major consumables (water and power). I've done a lot of "dry" camping (no hookups) in my class B motorhome (basically van sized) that we tow a small utility trailer behind (we use a Space trailers (http://www.spacetrailers.com/), they work well for us in that role). We also have an 85W solar panel which we use to top off our battery during the day (12V AGM 45Ahr lead/acid). There is a small 1kw honda generator (quiet) which we can use if we want to use the microwave or AC when we're not connected to power. Fridge and stove run on propane. We have two battery boxes (basically an ice chest holding an AGM lead-acid battery and a power inverter) which we can use in camp to run lights or fans away from the camper. The solar panel set up lets us use it to charge any of the batteries.
Ok, so there some meta considerations. One is that most trailers and RVs are designed to be compact "living" spaces, and are not set up for "working." In my sketches I've got the dinette changed to be convertable between dinette and workspace (giving up the extra bed). With my current camper I have been known to write code with my macbook in my lap or on a picnic table. What I don't have is good network connectivity.
You can make a lot of progress by making a log of your typical "work" day for a week or so, in both good weather and bad, and then going back over that log and taking each day and describing how you would spend that day if you're living space were this trailer. What things would you need the trailer to provide, what things would you substitute.
If you're primary goal is to avoid the "high cost of housing" then you probably need to scope out where and for how long you can park your trailer while you live/work in it. Camp sites will often have continuous day limits (like 14 days in California state parks) RV parks you can go longer but you have to figure that cost into your 'burn rate' as well. That said, one of the features of 'trailer park living' has been the low overhead.
Feel free to contact me offline if you have more questions (mail is in my profile)
It's less about saving money than it is about minimizing a bit, and seeing more of the country.