Home Network setup using cell data

There are several questions in there, and some of them indicate misleading impressions.

There are several ways to set it up, and I would suspect that having a dedicate hotspt device might be a better coice than using your iPhone, for doing what you are thinking. That would allow you to use your phone for somethign else at the same time, or for you to leave with yoru cell phone while yor computer is downloading something at home.

Many people still use the microcell devices, but those are used to use your existing home internet connection to suppliment a weak cellular signal. If you cancel your home internet service, you can't use a microcell device. Worse, if you ar eusing a microcell device, then your plan to use your cellular data to replace your home internet will fail because you don't have a good cellular signal at home so you can't use it for yor home internet connection.

Lastly, with the Mobile Share plans, you don't get throttled. If you exceed your 10GB subscribed limit, then you pay $15/GB for the additional data you use, but it is still provided at the top speed possible with your equipment and location. If you may use more than 10GB, then this could get very expensive for you, especially is you do anything via your home computer on the internet. Keep in mind that the most recent iOS update is over 1.5GB if you download it using iTunes, so that would eat a huge chunk of your monthly data allotment.

If you are serious about this, be very aware of how much data you are actually using for your home computer, and make sure that the overage charges will not cause your "great idea" to suddenly cost you hundreds of dollars in overage charges...