I am 21 yrs old looking to purchase a multiunit property. Advice?

[Andrew Michaud]

O am 21 years old living in Maine. Very interested in a 4 unit apartment complex with additional commercial space that is currently a turn key beauty salon in business. All 4 units are occupied. Four 1 bedroom 1 baths. In a small town in Maine. This place is in very good shape. This place will have 50% equity room. Purchase price is 60k, valued at 120k. Seller is old with prostate cancer looking to free up some responsibility. Real estate is cheap in maine so don't be surprised by the figure! 

More importantly, my situation is.. I have never financed for any sort of mortgage. Tomorrow I will be attempting to finance to purchase this property. My credit score is currently 780 which I feel is excellent for my age. Past two years I have made 50k gross income, but currently my only proof of income today is a part time job making 15k gross per year. I have a 10k loan on a 25k valued truck. I also have 20k cash. What are my chances of getting approved for this loan? What are my financing options? What sort of rates and down payments should I expect to see? My biggest worry is my current income of 15k annually. BUT this property will be bringing an income on its own. What position am I in to purchase this property?

Thanks!