We grew bluberries when I was a boy. I'll tell you what I remember. You need the right variety, consistent water, good drainage, a complete fertilizer program, occational fungicide application, acid mulch/soil, and pest control. One of the most important elements is a fertilizer high in potassium and phosphorous (such as mono-potassium phosphate (0-30-15). We lost a lot of plants to root rot before we started using that fertilizer (even with what appeared to be perfect drainage). Potassium makes roots more resistant to disease. Another similar product that a lot of blueberry growers used was Nutri-phite (0-26-28). They will need some nitrogen as well from a balanced fertilizer (we used a time release such as ozmocote or multicote) and a source of minors (Keyplex makes a special blueberry formula). Acid mulch (such as pine bark fines or pine needles) is also helpful. Keep in mind, too that productivity drops the further south you get from I 4. If you are going to do all the work to grow them, I would start with 20 bushes. Planted 6x3 they will take up the same space as 1 fully grown mango tree and it is not that much more effort to care for 20 as compared to 1 or 2 and you will actually get a meaningful amount of fruit. I would also invest in bird netting. Once the birds find you its game over if you only have a few bushes. When we got out of blueberries, we kept about 50 bushes for personal consumption. In the years we don't net them we might pick a handful of berries that the birds missed when they got ripe. Finally, blueberries are not long lived in south Florida and need replaced about every 15-20 years typically. With the prices of plants these days, you may want to learn how to propagate your own from semi-hardwood cuttings.
