Jared,
What a great plan! You would not be able to obtain a loan on your own until you meet the following:
1. Are at least 18 years old.
2. Have a steady income for at least 24 months.
3. Have a credit score of at least 640. (The higher your score, the better your interest rate will be).
Or you need to have a qualified co-signer. Generally speaking, the bank providing the loan will require the co-signer to also be on the title to the property with you.
Here is some basic advice:
1. Becoming a realtor. Most realtors are self-employed, and write off a lot of their expenses. Writing off everything you can might be tax smart, but does not help you qualify for a loan. I would suggest getting an entry level W2 job at a local real estate brokerage. You can learn a lot and possibly have your license paid for. This can be a reception job, marketing job, transaction coordinator, realtor assistant etc.
2. Build your credit. One way to instantly get credit is to have a responsible adult with good credit and responsible credit card usage add you as an "authorized user" to their account. If this option is not available to you, you can get a secured card through your bank or credit union. They basically have you set up a savings account that will pay the bank if you default on the credit card. After 6 months to a year, you may be eligible for a regular credit card, and then they would close the account and send you the savings deposit back.
3. I recommend reading Dan Sheeks "First to A Million: A Teenager's Guide to Achieving Early Financial Independence. It will give you a more in-depth plan on all of the above.
Good luck! I think it is brilliant to start so early! :)
Melissa