The only thing that is important is that the azalea gets enough shade. They like partial shade in hot climates. Some varieties need more shade and some varieties will not grow in a hot climate. They get a disease that kills the roots.

First you should find out how much sun the variety you are planting needs. Most like partial shade. They need some sun to set flower buds, but some shade to keep the roots from cooking. Mulch is also very important to keep the roots cool.

To increase your chances of success, make sure you have a well drained bed. Sandy soil is very well drained. If the soil is not well drained, plant in a raised bed to insure good drainage.

Here is a link that might be useful: How to care for rhododendrons and azaleas.

As far as shade, they will get some afternoon sun. Perhaps there is a variety that likes that?

Sandy soil is ABUNDANT here! I am not even sure if you can call our soil...soil.