I sold my sailboat that was anchored in Luperon to a guy who flew in from CT to see it. All was U.S. registered so it was hermano a hermano with no Dominican involvement, which is always best if possible.
-Make a deal with a 24h gas station on busy street (between Sosua and POP or Santo Domingo Las Americas Boca Chica)
-Do not waste your time in Luperon
-Visit Andres Marina
-Pin up posters in Marinas (even at Montecristi)
-Prepare a webpage with all details.