NEW HAVEN, Conn. (WTNH) — Many of us only look for one thing when our taxes are prepared: how much do I owe or what am I getting back? But the experts suggest you look at a lot more so you can catch any mistakes before the IRS does.

They’re the professionals, but it doesn’t mean mistakes won’t happen when you file your taxes. Eric Green is a tax attorney at Green & Sklarz, LLC. who sees mistakes on professionally prepared returns that cost taxpayers big money every year. Sometimes it’s because ex-spouses aren’t on the same page.

“The problem is, one takes everything as alimony and deducts it all, the other claims it’s child support and doesn’t put it on their return. That mismatch inevitably triggers an audit,” Green said.

Also, he says business owners who are sloppy with their record-keeping shouldn’t “guesstimate” their business expenses. Neither should you for charitable contributions.

“How much is the clothing really worth you know but people put down all kinds of money or their practitioner does,” Green added.

Green says mistakes like these can cost a lot of money.  You could wind up paying a 20% accuracy penalty, plus interest.  If you get audited for one year, they’re likely to look at other years. More mistakes, more money.

Green says the IRS will treat you as if you’ve looked at your return, so it’s a good idea to do that.

You want to get all the contact information you need for your preparer too so if the IRS does come after you, you have their help. Never let a return be submitted without your preparers professional ID and signature.