Hello
@terry_evian and welcome to the forum. As you said there are plenty of options and plenty of ways to apply those options too, as many members will attest. But first of all, for off grid power, you need a good AGM battery/ies. A good 130ah AGM can be obtained on Ebay for $250.00 to $300.00. Then you need to be able to charge the battery/ies. Portable folding solar panels are now relatively cheap. You can get a 200 watt version with a cheap PWM controller for around $130.00 delivered. These are fixed glass type. and weigh about 12kgs. Lighter folding type are around the $280.00 mark and sometimes do not have a controller which may have to be purchased separately. An MPPT controller is far more efficient but costs around the $150.00 mark for a PROPER MPPT type with a display screen. Other more sophisticated types need a separate display screen but can be connected by blue tooth to your phone.. The skies the limit. Things to consider are your daily power usage and storage. More panels gives quicker recharging, but more batteries provides better storage when recharging is not real good because of cloud or rainy conditions. Lithium are great but will well and truly blow your budget!!!
Then you have to consider weight, storage capacity in van when travelling and various connections to exterior of van for solar panels. If you are knowledgeable on 12 volt electrics, then there are plenty of posts on this subject on this forum for you to read about.
My system came in well under the $1000.00 you are thinking about and I only have a 2013 Penguin and a single 120ah AGM, now 8 years old. I have 1 x 180w, and 2 x 200w folding type solar panels connected in SERIES. My daily power use includes lighting (all LED type) electric computer fans in both 3 way fridges, charging by USB connections for phones, I pads, and rechargeable LED lights. Probably extravagant use at times. Daily power averages 37.0ah and is easily recovered by solar panels before midday, and after that the MPPT controller just goes into Float mode and handles any other loads that come on. I do not have a compressor fridge only a 93L Thetford 3 way which runs on gas when off grid. I have attached a few links on Ebay for you to think about. I hope you find them useful and at least some sort of starting point. Good luck!
I assume your van Fridge is a 3 way Absorption type and not a 12 volt compressor type. If so, then even more storage/charging is definitely required. The 90l Waeco running continuously will draw approx 2 to 3 Amps per hour, and so working on a 50% on/off cycle, power usage will at least 35 to 45 ah per day on top of all other usages. You will have to consider Waeco fridge demands carefully.
The ATEM POWER AGM battery, which has built-in pure lead grip and AGM separator for enhanced conductivity and electrolyte absorption and effective charge keeping, is all weather- and temperature-resistant, and this battery is also designed for a more efficient discharge recovery. Faster...
www.ebay.com.au
https://www.ebay.com.au/itm/12V-200...Caravan-USB-Controller-Charging-/293580686588 (not a proper MPPT controller!!!) but panel looks good.
https://www.ebay.com.au/itm/LDSOLAR...172144?hash=item2ab324fcf0:g:vuAAAOSwF2FbrbjP
There are good Epever models too, but you need to buy some peripherals to get the most out of these models and that costs extra.. Personally, I have similar panels to those listed and I also have the MPPT controller listed too which has all controls and settings available on a display screen so no need for extra accessories. Chose wisely, as the need for power grows the more you have it. And hopefully, you will be using these sort of things for many future off grid camping trips. Modifications to meet your own demands and custom is the name of the game.