Alignment shop wants to start with front sway bar only??

Have you weighed your RV loaded as it would be for a trip?
If you do not have at least 80% of the max front axle weight on the front axle it does not matter how much money you spend on alignments, steering stabilizers, shocks, sway bars or exorcisms you will have handling problems no if ands or buts. In addition without knowing your weights your tires are probably not inflated correctly and that can also cause major handing issues.