[ruthless]

^+1 to what dukes said

You will not be able to work(legally) in the US without a valid work visa. This isn't something simple to get either.
Also its in your best interests to not lie to them at the border. They can and usually will bust you. I suggest doing things the proper way, then you and your uncle have nothing to worry about.

Also if you are going to be going down, I suggest you strongly consider a medical/health insurance plan that will cover you. If something were to happen, you will pay for it big time.

You can stay in the U.S. as a VISITOR for 6 months. This is what the snowbirds who go to Florida do. Then leave(come back home) and the 6 months as a VISITOR start again.

As for the phone, WIND has unlimited data/calling in the U.S. it might be cheaper for you to buy a wind phone/plan, potentially?