Your financial aid package from FAFSA and the school includes tuition and associated expenses (rent, food, utilities, books, medical supplies, etc). Most schools will have some type of worksheet that you can use to help you see where you money is going your first semester and develop a set budget. They will tell you how much they allot per month for living expenses. For instance, at my school I think it's around $1200 a month for expenses (during 1st year) - however - this amount is figuring for a 9 month school year and most students will have to pay rent during the summer months. So just be sure to realize your money will have to stretch out over the full year (sounds simple, but a lot of students end of falling short because they think they can spend the full month's amount each month) then have nothing left to pay rent over the summer.
Also realize that a lot of schools do NOT allow extra money for residency interviews during your 4th year. My school recommends students put extra money aside each year so that you have enough to cover those expenses when the time comes.
I wasn't aware of the ability to loan out extra money - most schools have a set maximum that you can loan out for the school year (their set "cost of attendance"). You may want to check that out.
