I have towed a Impala on a cart, two full size Tahoes - four down (one half way across the country) and now a Lincoln MKX - four down. Learned a lot. I'd go 4 down and no cart. So far - my best choice - MKX, four down, a Demco tow bar - light hook up directly into the vehicle to use the signal lights on the car....no light bar - a electrical umbilical charge setup. Blue Ox brake system.
'05 TS DPusher (Model - Travel Supreme - Original)
'19 GRAND CHEEROKEE - Demco bar
"Over 40 years later....still on our honeymoon" ....Different Motorhome.