You can send any documents from here  like your apartment lease, your vehicle registration card, a request letter to the consular blah blah blah..................Your parents are applying for a visa to attend your graduation so I dont think its a good idea to show your bank statment and all other craps. First of all you havent graduated yet and you already have all kinds of money in your account. I would think about that. Here is what i did and the basic documents needed to apply for the visa for graduation for your parents:
                             - Your I-20 (updated and signed)
                             - Your Passport/Visa/I-94 photo copies
                             - Invitational letter from school
                             - Financial documents from Nepal (source of income,bank balance, property evaluation)
                             - you can add some documents to reflect your good academic standing (transcript, any accolades you won)

These are the basic documents that a parent need to submit. Anything besides these are just a way to console and convince your self. Good luck!!!