Hi! you can create a configuration be very similar to mine, with just a couple of changes.
But your first step should be to estimate your maximum daily power usage between 4 PM and 10 AM (daylight savings time) - the 18 hours when you will tend to run down the battery, rather than charge it up from solar. About 3 hours on either side of 1 PM will operate at a "profit", with solar power refilling the batteries.
If you will be under trees during that time, your solar production will be severely curtailed. You might also want to double that power figure in order to assure an extra day of capacity to "make up" for cloudy days, or you might bring along a generator to handle those days (partly or mostly cloudly.)
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Your DC-AC inverter will need to be "pure sine wave". Buy an Inverter with twice the continuous power rating which you expect to use for short periods. But I have a special warning regarding inverters: Do not try to use a MICROWAVE OVEN rated at "900 watts" or higher without an inverter rated for at least 3000 watts continuous. Microwave ovens have extremely high "reactance" -they attempt to pull power out-of-phase from the "120 volt, 60 cycle AC power supply, and they also try to kick some of that power backwards.
In a house connected to a gigantic grid, those variations don't matter as much. But in a tiny trailer, where the "grid" is just a small inverter and a few batteries behind it, that reactance can cause the inverter to fail - permanently. If you can avoid a microwave, and also avoid other high wattage DC appliances, you can get by with la smaller inverter, smaller inverter wires from the batteries, and probably smaller batteries as well.
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The "factory solar" of those days had one small panel feeding into a very simplistic "solar controller". The only job of that controller (and others of the same type, called "PWM") was to reduce high voltage power from the panel reaching the batteries at that high voltage. They provide only battery voltage (between around 14.0 and 13.3 volts, depending on the number of "modes" they use), throwing away all of the panel power being offered at higher voltage.
At around 200-300 watts total panel power, it becomes a smarter choice to buy a solar controller of type "MPPT". With these more expensive and complicated devices, extra power being offered from panels at higher voltage is converted into MORE CURRENT at battery-acceptable voltage levels. For example: In the case of a 20-volt panel offering 10 amps (a "200" watt panel), a PWM controller would offer only 10 amps at maybe 13.6 volts (total power of 136 watts), while an MPPT controller can offer about 190 watts. It can raise the battery output current to almost 13 amps, while still keeping the voltage low.
You want that. For the case of multiple panels, you can also wire them in series. In "series", the power into the controller is the current of the lowest panel times the sum of all voltages. In "parallel", the power into the controller is the sum of all currents times the lowest voltage). Wiring in series lets you use smaller solar wires over perhaps longer distances.
You can choose panels according to your possible rooftop mounting locations, their total weight, and the difficult of arranging the wires. So-called "flexible panels" weigh much less (allowing easier shell lifts), but they are easily ruined by hail storms. They cost more, and they tend to die young for no reason at all. Traditional glass-framed panels are much more durable and they cost less per watt, but the weight begins to add up fast.
I own both kinds, with six flex panels on the front shell (rated 600 watts total, though never performing better than about 450 watts maximum due to sun angles versus the flat roof). On the back, I have a single larger glass panel 200 watts, also offering only 150 watts maximum on perfect day in late June. I have huge and very costly batteries, but I run the air conditioner a lot.
I recommend an upgrade to LFP batteries, total size adequate for 2 days usage. Keep in mind the AGM or SLA batteries should only be used over a range of 50% nominal capacity, while LFP batteries can be used more than 85% each day - for thousands and thousands of times. 280-400Ah total size might be adequate for that. But LFP battery cells can only be charged in temperatures above freezing. A decent BMS ("battery management system") must be used and programmed to avoid charing below about 35 F. (The good ones have monitoring and programming from cellphones via bluetooth, and the signal for my BMS units goes right through the aluminum-clad TM walls.) I keep my 2619 battery inside, under the dining bench, to keep it warm in colder-weather camping.
