Here is a list of options, in order of increasing features and cost:

For a simple weather station (on the roof) and a console displaying the weather data in one room, all you need is:
Davis® Vantage Vue Wireless Weather Stations (DWVUE)

If you want to display the data on the internet, so everyone can see it, and do not need the console in the room, your can get our Davis® Vantage Vue Wireless Weather Stations (DWVUE-LWOC), which is for the Integrated Sensor Suite (ISS) and Weatherlink Live to allow you to post your weather data on the internet. No console

If you want both the data on the internet and a console displaying data in your room, you can instead purchase our Davis® Vantage Vue Wireless Weather Stations (DWVUE-LWC).

We also have the more expandable Davis Vantage Pro2 Wireless Weather Station (DWVP) and Davis Vantage Pro2 Plus Wireless Weather Station (DWPLUS) weather stations.