Ok so you know that a 501(c) organization or simply "a 501(c)" is an American tax
-exempt, nonprofit corporation or association. Section 501(c) of the United States Internal Revenue Code (26 U.S.C. § 501(c) ), provides that 28 types of nonprofit organizations are exempt from some federal income taxes. Sections 503 through 505 set out the requirements for attaining such exemptions. Many states refer to Section 501(c) for definitions of organizations exempt from state taxation as well.
You can have raffels and auctions but its a tricky process as to what you can use the money for, just save receipts as well as who the doner is and talk to a tax professional as i am only a Private Equity investor and not a CPA. I hope that helps some..