I had the same issue which can impact your fun meter. To solve the problem which means I made it more manageable for me I took the following steps:
1.Replaced the power converter to: PDI Inteli Power PD9160 - I charge through the trailer converter.
2.Replaced the 12v batteries with two 6 volts - I stopped killing 12v batteries.
3.Replaced lights with LED's - made a big difference in overall lighting and improved battery life
I have had consistent results as follows:
1. In warm weather battery power remains above 12v for 7 nights - no charge needed.
2. In cool weather with limited heater use I typically need to charge by the 4/5 day depending on outside temps.
3. In cold weather with temps in the 30's at night and 40's to 50's during the day and/or with snow on the ground I am charging twice a day morning and afternoon for 1 hour duration's. With snow on the ground the inside temp hovers around 55 degrees.
As stated these changes have made the power issue more manageable for me. People power management, climate and trailer systems draw would be different with each trailer. My mother has a Komfort FW with the same batteries and similar converter that draws more power and requires charging every other day in warm weather. It is no fun when cold.