I'm not concerned if a scratch the car, and I can use wood or something to help. I need to transport a regular household-size refrigerator. We don't have one, and occasionally people give them away on Craigslist. I also need to figure out a way to lift it to the position on the car.
There is no safe way to do this. Please don't try. Either have a properly made hitch installed and rent a small trailer, or rent/borrow a suitably sized truck.
You need to get at least four healthy strong people to get it on the car. You get a couple of long pieces of material like 2x4's or 4x4 lumber. You place the wood under the reefer in a manner that allows you to straddle the car, just make sure the lumber is long enough and strong enough, and that you have enough people to get the reefer high enough for long enough to get it on the car.
I would be really apprehensive about the weight of the thing, and the pressure of securing it properly, collapsing your car roof leaving a huge dent. I would suggest you try using a mattress to cradle the reefer.
There is a similar post about securing loads on cars here. , it may give you some food for thought.
Get a roof rack. Found one for a Taurus for $30 en ebay.
(this is an example of how not to do it btw)
Now, the roof rack comes with a manual in which is written the maximum weight. Mine can carry 70kg. Obviously, whatever you carry should be fastened properly. Please don't use rubberbands, or anything which has links made of plastic. Tough straps like this work very well:
For fragile materials (like sheetrock/gyproc) planks or a bit of plywood should be used to support it from below. Also, cardboard is needed to protect the sides and prevent the straps frop digging into the material. You should do this with your fridge, else the two beams of the roof rack will dent the edges when you fasten the straps tight.
You can put the flat plywood against the trunk of the car, lean the fridge on it, then slide the whole assembly onto the rack. It really helps to have some kind of ramp to haul the stuff up instead of just carrying it...
Now, the problem will be to put the fridge on the car. If you remove the shelves inside and unscrew the door, it will be lighter. This should be easy to do for 2 people.
And drive carefully, like 70 km/h...