You will need a lawyer to do your 501(c)3 paper work for the IRS. Anyone that donates to the organization is going to need a copy of that so they can show the IRS you are indeed a non-profit. Until you have that, you aren't one.

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This and other misconceptions are common. There is a difference between being a nonprofit (per state law) and a public charity (irs designation). Boardsource has good information and Nolo has several books that are worthwhile. Always nice to have an attorney on the board but not actually necessary.