No, I haven't seen anything that does it correctly. I figured there would be a few contractor type choices but could not find any.
The question to answer is what amperage (in total) do you want available inside the RV?
A simple 30A to 15A adapter coupled with a 3 outlet tap gives you multiple outlets for maybe $5 spent:
Again, you are limited to 15 amps in total (even though you see three 15 amp outlets) and you are missing important circuit breaker protection.
If you plan to run more than one item totaling more than 15 amps then some sort of electrical panel or sub panel is needed to give you more than one circuit.
If you plan to limit your power requirements to no more than 15 amps at one time then a basic 15 amp extension cord will give you up to 15 amps in the coach. Remember that you could easily overload the 15 amp cord if it is plugged into a 30 amp outlet and no circuit breaker will be there to trip to protect it.
