Will I need a cosigner?

So, I am 23 at the moment, and I have begun my car research. I have checked my credit score this year, in early March, and I had a score in the 700s. I have 4 credit cards, 2 of which are store specific. All are paid on time, and no debts on those. I do not like to have outstanding balances. I do have a school loan under my name at the moment, by the end of the program, it will be around, 30K.

I would like to purchase a new (used) car in the next 2-3 months. While talking with my family, and knowing that both my brother and father will accompany me when I go to the dealer and actually pick, test and ultimately purchase the car. Both of them are mechanics so unless they say I can test it out, I am not getting behind the wheel no matter what the dealer might say.

I do plan on giving between 3 and 5k down as a down payment, and I am looking for a car that is under 30k in price. I have a few in mind and I am doing quite a bit of research in what I want in my new car and what I expect to be paying.

I do have a steady job, and I will have been at the job a year in Feb 2014. But my previous employer was actually the City I live in. I do make a sufficient amount in income.

Will I need a cosigner when I do go in and begin the purchasing process? Ultimately, I would like to be able to make the purchase and drive off the lot without having a cosigner. Are there steps I can take right now to make sure I am in the clear?

Thank you in advance to all replies, however if you are going to comment about why I should not waste my money on a newer car when I can purchase an older car for cash, I already did that, the amount of money that went in the car after things started going wrong surpassed the retail value of the vehicle and both my father and brother worked on my car numerous times and they both said it is not worth it to do that again and leave me without a car. I need a car for work so I need something in real good condition. I would rather pay a monthly amount for a few years and be covered with a great car, than pay cash up front for a car and then put in more than it is worth.