Ben,
There's nothing wrong with keeping the 900 for a while. I know how bad you want the Busa, but maybe it's just not the right time yet. Oh sure...we're gonna give ya some shid about riding a little 900, but it's all good
I skimmed through most of the replies, so forgive me if I'm repeating other's ideas.
A dealership can loan between 100%-120% of MSRP on a new bike. This would help pay off your bike and finance the new one, BUT... That usually comes with a higher interest rate because you are now a higher risk to them if you should default on the loan. They have to look at recouping their losses through an auction, therefore the higher interest rate gets them their money back faster.
You might want to talk to your bank about a small signature loan to help establish some credit. Something like $500-$1000 dollars.
DO NOT spend this money. Take the money and put it into a savings account, then have the bank automatically take the loan payments out of this account. The money will gain some interest which offsets the interest rate of the loan, and you are establishing credit by having a loan and having a good payment history.
This may not help you with getting the Busa you want right now, but it will put you in a better position to purchase what you want later on.
Good Luck
BTW: Keep your chin up Ben...we've all been through it...it gets better