Tow dollies are a 700# PITA. Some RV parks won't allow you to store them at your site and require that they be parked in a seperate area. That means you unload the car, tow the dolly to the storage area, disconnect and drive back to you space to park. Other parks, and they are plenty, have pull through spaces so you don't have to disconnecct for one night.
They (Tow Dolly) also use a ball coupler type hitch. I don't know the GVW of the Murano, but I'm sure it is more than 2000# and with a dolly you are looking at the mechanical connection keeping the vehicle attached to the dolly and the mechanical connection of the hitch.
If it is just an overnight stay, that becomes a hassle (connecting the dolly, off loading and re-loading). That is why I bought a vehicle that can be flat towed. Again, look at towables here MotorHome Magazine: Making your RV travels easier
You will need a tow bar and bracket instaled on the Towed vehicle, mine are invisible when the brackets are removed.
Diesel or gas, you will have no problem towing, however; it is a horsepower and torque to weight issue and the diesel have the gas unit beat in that department. They also last longer than gas engines and command a higher resale value. Here is one, but it has 130,000 miles for $33,495 1998 Allegro Bus By Tiffin 32 BUS DSL for Sale - D766