@L Alan Williams Hi, Alan! This is Mrs. RockyM. You have to start the residency process from the US. The Consulate in New Orleans will be the closest one to you, but their website stinks! Here's a link to the Consulate in Washington with the info you need to apply for a Residency Visa: DR Consulate on Washington.
Once you get your residency Visa, you have 60 days to enter the DR and submit your full application for residency. More information on that can be found on the website for Migración.
Having an attorney is very beneficial! We used Lishali Baez. She is excellent! You can reach her at 809-860-1231 or lbaez@lishalibaez.com.
Once you have your residency, then you can arrange for shipment of your household items and get the tax waiver from Aduanas. To get that exemption, you must ship the container in within 6 months of gaining residency.