Sorry for the blurry pictures. Here are the leaves.

It seems that older stems develop bark, and younger ones are green.

Here is the whole plant with a chair for scale.

The soil here is probably somewhat acidic. Thanks for looking. Let me know if better pictures are needed.

That is a type of Vaccinium - blueberry. Perhaps Vaccinium corymbosum. A great family of shrubs. Leaves turn bright red here in fall.

Thanks. I did some research and found a list of Vaccinium species native to Florida (from online Atlas of Fl Vascular Plants).

V. arboreum
V. corymbosum
V. darrowii*
V. myrsinites*
V. stamineum

*It's definitely not V. darrowii or myrsinites, and probably not V. arboreum. The dwarf blueberry and sparkleberry are pretty common in my yard. My neighbor had quite a few native blueberries in his yard so they must do well here too. I used to go over and pick them sometimes. But, he is a lawn person and ended up clear cutting most of the native vegetation.

Here is a link that might be useful: ISB: Atlas of Florida Vascular Plants

It's not arboreum, that has much more rounded leaves. And it's not stamineum, that has more horizontal, almost layered shape. I agree it's not the other two you already ruled out either.

That just leaves V. corymbosum, I guess. Too bad about your neighbor. ;)