Hi There.
Here is what we ended up doing.
We purchased a 30 foot 30 amp extension cord and a 50 amp marinco female connector. I cut the female end off of the extension cord and put the 50 amp connetor on. You have to add a jumper wire from the Hot ( black wire connector) to the (red wire connector) in the 50 amp plug. A 50 amp service actually supplies two 120 volt circuits to your trailer. If you don't add the jumper only half of the circuits work in your trailer.
It does the same thing as pluging the 50 amp to 30 amp adaptor to your 50 amp monster cord. in that case the jumper is in the 50 to 30 amp adaptor. It seems to work great here in our driveway, and You don't have to man handle the 50 amp monster cord or use a bunch of adaptors.
Take care and thanks for all the info
John & Dawn