I used a tax expert to help determine the right way to report my rental property mortgage interest - it was great because she gave me confidence that it wasn't going to get kicked back to me for correction. I also used a tax advisor to help with some complicated filing issues around dependent children when one of my two kids is claimed by my ex-husband. Even when there's gray area, they are able to give guidance to make the best choice and take action or at the very least, understand your risks.