There should be an encyclopedia dedicated to this subject. There are tons of articles, references, and warnings on the Internet, and it is probably the most prolific source you'll find (and perhaps the most confusing).
What tends to happen right out of the gate is that good folks like yourself end up calling a number they find on a website and find a friendly, helpful individual on the other end who promises you a quick sale and an easy path to success. What you might end up doing is signing up for their services and dolling out a few hundred dollars for their service. This is where the problems starts. Resales are very difficult to achieve, and a large portion of units go unsold for months and years for many different reasons, e.g. over priced, undesireable unit, resort location, and or program features. So many factors go into this that you won't find a single solution to your quest. To start avoid this outlay of cash unless you want someone to take your troubles off your chest. They won't go away, but at least you will have someone else working on the issue (if you find a respectable service).
To start, put some feelers out on the Internet. There are plenty of inexpensive, or free, sites that can at least get you some idea what your unit is worth, and if you over price your unit on a free site, you haven't lost anything, except time and the potential of another annual maintenance fee. You can use this site and take advantage of our performance based system. It is one of the more equitable solutions on the net, but not the only one. Spread your ad around, but if you aren't up for spending any money up-front stick with the sites that don't charge to place your ad.
Where's your resort? What's the name of it? We have put a lot of information on this discussion board regarding how to promote your resort. Once you place your ad, write a review, start a discussion about the resort and add a link to your ad. Start discussions on other boards with links to the same ad. The more you talk about it, the more exposure it will get. This discussion board will not discourage an open discussion about your resort. Did you enjoy it? Tell people about it. Try renting it, too. You may find that a casual vacationer may fall in love with the place and want to negotiate a deal following their vacation.
To summarize:
1. Minimize your cash outlay to advertise.
2. Maximize your exposure on free and inexpensive sites.
3.
Place an ad on this site.
4. Write a review on this site. Your ad will end up on the review page via our RSS feeds, so you end up with twice the exposure right out of the gate with very little effort.
5. Start a discussion just like you did with your question. Use a title like, Palm Oasis, views and reviews. Ask a question like, "Has anyone else ever been here?" Get people talking. And then add a link in your discussions to your ad page so people can see your ad.
6. Do the same thing on other boards that will allow it.
7. If you decide to go with a broker, don't also pay a fee up-front. They'll get plenty of the proceeds from the sale to make it worth their while. Their incentive will come from the sale; it will take the load off you, but you'll pay up to 30% of the proceeds in commissions.
Good luck!