Got ya beat! We're 74 years old.
Leveling a trailer using wood blocks isn't hard, then use the screw jacks to stabilize the rig.
The hitch set up is important and yes, it can be heavy. When hitches are adjusted correctly, they work well.
Our Outdoor brand trailer has 80 gallons fresh water, 80 grey, and 40 black. It's 30 ft long bumper to hitch, and is pulled with a 3/4 pick up that gets 8.5 MPG. We have dual pane windows, lots of storage space, and don't have to listen to rattles when we drive.
To be honest, going to a tow behind or fifth wheel would be a learning experience, but very doable if you're ready for a new way to travel.