Mr. Pinky,
Look in the owner's manual to see what the instructions say about towing behind a motorhome.
In my opinion, you are in a perfect position to purchase a vehicle that can be towed four down from the factory. I would not go to the expense of buying something that would need alteration like buying from Remco. It's just more added expense.
Motorhome Magazine's towing guide from 2015 says that the Lincoln MKZ and MKZ Hybrid are towable four down.
The thing about towing a sedan is that they sit lower to the ground than a SUV. My thoughts are if you have to straddle something in the road in the motorhome, you don't want it getting hung up under the toad. As I'm sure you know, you will be dodging stuff from time to time from tire rubber to things that have fallen off trucks/cars from bad loading.
Safe travels,
MM.