Non profit taxes

hi! I am the director of a charity 5k. We send all of our proceeds to a registered 501c3. Last year we raised over 23k and just handled the funds with our own bank account (kinda sketchy collecting people's money that way). We are wanting something a little more professional and safe for future years. BUT- we are hesitant to start an LLC or business account because of the taxes. 

 

What would the taxes look like if we created a business to collect charity funds? And how much donated money would we lose due to business fees/taxes?