In certain cases where you have repaid some installments of a previous student loan independently, you would be given the authority of branching away the Co-borrower. This is known as Co-Borrower Release and by doing so, you ensure that the loan repayment is entirely yours. This also puts you in a position where you are not hit by the Credit History of your Co-Borrower. Both of you are separate entities speaking from the loan perspective and you would hence need to take charge of repaying your loan off.
For commercial banks and large finance companies, "loan agreements" are usually not categorized although "loan portfolios" are often broadly characterized into "personal" and "commercial" loans while the "commercial" category is then subdivided into "industrial" and "commercial real estate" loans. "Industrial" loans are those that depend on the cashflow and creditworthiness of the company and the widgets or service that it sells. "Commercial real estate" loans are those that repay loans but that depend on the rental revenues paid by tenants who lease space, usually for extended times. More granular categorizations of loan portfolios exist but these are always variations around the larger themes.
Start your research today and trust me, you will find one or the other lender who will be able to give you a loan without your co-borrower. Please note that having or not having a co-borrower for your loan is subject to the credit history of your co-borrower. If he has a good credit history, you would not mind getting him on-board for signing the loan agreement. Think twice if it is otherwise.
There are many financial institutions that offer private student loans with bad credit. The only fuss in the deal is the requirements of the financial institutions. Most entities that I know of providing this service would require a Co-borrower or a Co-Signer. This means as a student you and your parents would need to sign on the loan agreement agreeing to repay the loan.
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