I know exactly how it feels, I moved out of home it was my choice at fifteen. I am mature for my age though but to answer you question. (I moved towns)
There a lot of things, I wish someone had told me before I moved out.
Money is definately a huge thing, once you move out you take on a lot of responsibility you need to pay for rent, power, groceries.
Make sure you have stuff like kitchen utensils, microwaves, couches, beds, washing machine, table, etc, before you move out it's hard not having some of these things ESPECIALLY A WASHING MACHINE otherwise you end up spending so much money on laundromats.
Make sure you're completely ready, it is a huge shock and wake up call. It takes a month or two to realise "What you've actually done?"
Definately save! Have a reasonable amount of money saved so if you do get in trouble you have back-up and so you don't have rely on someone else for that.
DON'T MOVE IN WITH FRIENDS!
I made that mistake at first and it was a huge regret. You really get to know someone by moving in with them, and they can really irritating after awhile - remember a lease for a house is for 6 months. You're stuck with them for that long because you cannot get your name off the contract before the times up without paying the price.
Take the shortest lease available, you can always apply for it again if you liked it .. But you don't want to be stuck in a house you hate for a year.
When you do move out buy bulk; Washing Powder, Detergant, Cleaning Products etc.
Hope I helped in someway.
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