Sell off the doubles.
Not in lots, unless the buyer is someone like HD who has a lot of disposable income, you wont get much buyers for lot items, plus you lose quite a bit on lot sale.
As everyone has said, start with the least fave items, if not here have it on Ebay. Prioritize.
Keep your goal in sight - which one is it? Student loan or House? decide then stick to it. Plan with foresight - coz with a house you have enough space but do you have the means to maintain a steady mortgage? If you go for the loan, being a student would you have enough cash/income to sustain this hobby and be sure that what your studying for will end you in a definite job in the end, not some idealistic course where you'd struggle come graduation to find a job that'll suit what you studied for? or will you end up still selling more of your stuff?

Just some questions that you might have already asked yourself and hopefully have finally reached a decision with before you sell any more of your collection.