If you are going to move to the Caribbean, or you have a business which sells goods there, you need the services of a specialist shipping company that has experience of shipping to the area, understands the customs requirements and documentation that is needed, and can ensure that your goods get from the port or airport to wherever you happen to need them.
Whether you are moving to Jamaica, shipping to Grenada, or shipping to St Lucia, your goods and belongings will need specialist packing in order to ensure that they don't move about in transit and arrive the other end in the same condition that they left the UK. Certainly, you can save a small amount by packing the goods yourself but there are two main problems. The first is that you have to physically do the packing yourself, and the second is that when you are moving things such a long way it is far better to have them packed by trained specialists who do it every day rather than risk any damage.
Furthermore, when you are shipping to Trinidad or any of the Caribbean islands, you will very probably find that if you pack them yourself, they are not insured, or that if you have to insure them separately the premium will outweigh the cost of having them professionally packed in any case. When you consider the small amount of money that you might save on packing, plus the fact that you have to do it yourself, the cost of professional packing is a small price to pay.