Petehb has the right approach or at least the same one I use, my main difference is that my marker buoy has a little bit a writing on it telling anyone who picks it up and tries to moor on it that the fee is $150 per day.
Have had several numpties try to moor on it, mainly in the Grenadines and Bequia and the only thing that worked was the thought of coughing up large chunks of money. The boat boy moorings are $25 a night. Anchoring in most bays is free!
6mm polyprop is well upto the job of breaking out our 20kg Delta.
Youth is wasted on the young
Fair winds and beautiful sunsets to all who sail for pleasure