If you have high repaying capacity, then it is advisable that you opt for less number of years for repaying the loan as it will reduce the overall burden of the interest. Though you are ready for repaying the loan as quickly as possible, but if you miss to mention this in the loan agreement, it would be tough to alter once the application is processed by the organization that is lending you the money.
Loan agreements, like any contract, reflect an "offer," the "acceptance of the offer," "consideration," and can only involve situations that are "legal" (a term loan agreement involving heroin drug sales is not "legal"). Loan agreements are documented via their commitment letters, agreements that reflect the understandings reached between the involved parties, a promissory note, and a collateral agreement (such as a mortgage or a personal guarantee). Loan agreements offered by regulated banks are different from those that are offered by finance companies in that banks receive a "banking charter" granted as a privilege and involving the "public trust."
It is an unsaid rule in the world of loans that one needs a co-signer to ensure that the student loan gets approved. That said, it does not mean that you would not get loans if you do not have a co-signer to sign on your agreement. There are some lenders in the market who would offer loans to you with you having to worry about the co-signer.
If you have any queries in future, then you should be able to easily contact the lender. For this purpose, you should ensure that the company name, corresponding address and the phone number are mentioned in the loan agreement than the details about the agent who has been processing the loan for you.