I'm finishing my third year of college and plan to graduate with my undergraduate degree in the spring of 2012. Afterward I plan to enter medical school which is an additional four years of college. Student loans were inevitable in my situation, as I'm paying for college independently. I have a mixture of both federal and third party loans, most of which are being deferred, totaling to around fifty thousand dollars. Every year my school puts out a list of "preferred" lenders which tends to change from year to year. I'm now in a situation where I have four different third party lenders, and it looks as though I will need yet another distinct lender for the upcoming school year. When is it okay to consolidate my third party loans? Should I only consolidate my third party loans? What effect will consolidation have on my credit score?

Thank You,
Jake