Okay, so I put a solar panel on the trailer and just used the trailer for 3 days. First some specs
120 amps of lifepo4 battery
100 watt renogy glass panel
rich solar mppt charger ( same as the renogy but 20 bucks cheaper )
Started out with a fully charged battery, ran a car radio, usb plugs charging phones, a fan some, lights and my inverter for several hours powering a 120 volt 100 amp speaker/amp. the solar providing power during the day, most power was used at night. Each day was about the same, I used about 20% of the battery or about 25 ah by sunrise. The big part of that was the inverter after dark, and I woke each day to the 80% or 25 ah or so of used power. We only really used the usb and radio during the day and still when the sun went down the battery was basically fully charged.
The during the day usage was the radio at about 2 amps an hour, and the usbs. At night was about .7 amps on exterior lights for about 4 hours, and the speaker/amp for about 3 hours and its draw was between 3-6 amps depending on the music and volume. So the solar ran the stuff during the day and still charged me up.
Yes I know this is not the normal teardrop power usage with the inverter, but the other stuff is pretty normal. I built my power system to be able to handle this type of load and did like a champ.