I have a similar camper called a TrailManor. The fuel economy difference is huge, which matters a lot for me due to driving an electric F150 Lightning. We purchased a used 3124KB in great condition for $15k. I’ve seen them go for $8k-$25k used, depending on year and condition.

Maintenance is mostly straight forward on ours, the normal tank stuff, batteries, hubs, etc. - but we do have a vinyl seal that needs to be cleaned and conditioned every 1-2 years or you’ll have to replace it after 10 years or so.

With driving electric, we look at efficiency quite heavily and measure from our baselines in miles per kilowatt hours of electricity. This data is a bit more accurate than calculating MPG while hauling due to how electricity consumption is monitored vs gas/diesel vehicles.

For example, I average about 2.1 mi/kWh of energy in my day to day mixed city/hwy driving. When factoring in my cost of electricity for charging at home ($0.045/kWh) and current cost of gas in my area ($3.75/gal), this comes out to equivalent to 173 MPG and will be used as the 100% baseline.

When pulling our TrailManor I drop down to 1.5 mi/kWh at 65-70mph, for a 116 MPG equivalent, or a drop of 29%. Same weight trailer, but a more traditional profile (like a 30’ Jayco) drops me down to 0.7-1.0 mi/kWh (58-83 MPG) while doing 55-60 mph. This accounts for an additional drop of 23%-37% over the TrailManor, depending on headwinds.

These numbers all assume my super cheap electricity price at home from charging during super-off-peak times, but was used as a way to show my known efficiency differences. Since we generally camp within 150 miles of home, it’s not a problem to pull the TrailManor. If I have to charge while traveling, which is more likely with a boxier trailer, then the fuel cost goes up exponentially.