I am wondering whether there are 21 or so foot TT's which have a walk around bed. We had a Mallard 24' which did and loved it! Currently I have a 2012 Holiday Rambler Aluma Lite 21' which weighs 3450 lb and has a slide-out. The tow vehicle is a 2010 Chevy Traverse LT with tow pkg and so is capable of pulling up to 5200 lbs.
Can I stay under 24' and still have the walk around bed feature?
Absolutely, for example the Lance 1885 is a 23'9" trailer with a great walk around bed that has an option to also be a couch during the day. The 1985 is 23'4" in length.