Android as WiFi access point using Wifi rather than 4g

Question

I need to know if this is even possible and if it is how I would go about doing this.

I have a laptop, android phone, and Google ChromeCast HDMI adapter. When I am at home and on the same network as the ChromeCast I am able to broadcast by browser window to the Chromecast and thus watch what I am doing on my TV.

I need a way that when I am away from home and on a network that blocks devices from talking to one another to be able to do the same thing.

In order to do this I believe what I need to be able to do is have my Samsung sIII connect to a WiFi point where it has internet access, then for my computer and ChomeCast to connect to my phone on a completely different class c where they are able to access the internet but also talk to one another regardless of if the external network permits it or not.

I can do this by using the phones built in hotspot, but I don't want to use my phones data plan if there is a network I can connect to in order to use their internet.

In addition to using this while I am with clients to broadcast my browser screen, when I am travelling with my family I would like to be able to stream from my Netflix account however most hotels I have stayed in won't let the chrome device connect to my computer because of the AP isolation. Again, it would be nice to connect to the hotel wifi to stream netflix but to let the chrome device connect to the phone as it's access point so the phone can talk to the ChromeCast.

Any help would be appreciated!