The real estate industry is filled with victories, losses and mistakes. Over the years, many real estate and small business owners across the U.S. have witnessed numerous mistakes that have cost them thousands of dollars in overpaid taxes. Personal funds used for business and real estate expenses are nondeductible. If you have a legal entity from which to operate your real estate, make sure to use it correctly. There are still ways to claim many deductions from your real estate business, even if you do not take the home office deduction.