It’s very common for the branches of trees to overhang over neighbors’ property. Sometimes roots can also encroach onto neighbors’ property or trees may fall onto neighbors’ property.
What are the tree trimming and maintenance laws? Well it depends.
If the branches/trees/roots are healthy, neighbors, at their own cost, trim back encroaching branches and roots up to the property line. Damages on their property from encroaching branches or roots are their responsibility. The owners of the trees generally have no liability.
If the branches/trees/roots are dead or not healthy, the owners of the property on which the trees are planted are responsible for trimming branches and roots or for taking down the trees. The owners of the trees may be liable for damages from encroaching branches or roots, or fallen trees on adjacent properties.
You can find more information at UF/IFAS Trees and Landowner Responsibility
As always, it’s alway best to have an open discussion with your neighbors to figure out the best solution for everyone.