The UniFi AP family is a line of high performance wireless access points designed for both regular and high-density environments.
In addition to the basic functionality, UniFi APs offer features like guest portals, access control, multi-hop and others.
When picking the AP model, keep in mind that different APs have different radio rates, number of ports and concurrent clients and other differences.
You can also conduct a wireless site survey to get a true idea of the different areas of signal strength in the building.