Tip three: Accept Credit Cards. I hate, hate, hate paying merchant fees out of our companies hard earned revenue but for some customers that are habitually late or simply have small invoice amounts the easiest solution is to charge their credit card. Most small business accounting systems allow you to keep their card on file and simply charge their card each month and your cash is nearly immediate. One caveat – watch your merchant statement for exorbitant fees. One of our clients that had a $3,000/mo invoice charged to their card was using a corporate card that ended up with a 4.5% fee to us. After realizing that we were spending nearly $1,600/year in fees just to accept their card we moved them to invoicing instead.