I have designed and deployed various 802.11 WiFi deployments using solutions from Aruba, Cisco, Ubiquiti, Enterasys, Linksys, Asus, and HP. Deployments covered businesses, warehouses (which included scan guns), and homes.
Planning, Design, Validation, and troubleshooting of Wifi has been done with various tools including: Kismet, AirMagnet, and Ekahau. Planning often involved using floor plans and building materials (when available), to predict solution specific coverage patterns to find the right cost-to-features/performance to meet customer requirements.