Business and Personal Expenses Don't Mix - Financial Web"Perhaps it started out as just a way to spend a few weekends each month doing something that you like to do, and make a few bucks at it to boot. You probably never bothered to give much thought to organizing, much less turning things into a permanent enterprise. And, as such, all of the money you made from your little diversion simply went into your personal account. But then, things actually began to pick up and soon you were making money hand-over-fist. Here's where the fun begins, because the IRS now categorizes you as "self-employed" for tax purposes, and because your sideline occupation is pulling in more than $400 of profit a year, you have to pay taxes on it. Your single personal checking account is now going to make things more confusing for both you and your accountant."
You must file a Schedule SE (self-employment) if:
You had net earnings from self-employment from other than church employee income (line 4 of Short Schedule SE or line 4c of
Long Schedule SE) of $400 or more
In the USA, a sole proprietorship just means you add two new pages to your annual tax return. That would be a Schedule C to show your income and expenses, and a Schedule SE to figure your self-employment tax.
The official definition of a deductible expense according to IRS is that “a business expense must be both ordinary and necessary.” An ordinary expense is defined as one that is “common and accepted in your trade or business.” A necessary expense is defined as one that is “helpful and appropriate for your trade or business.”
High Income Means a Higher Audit Risk"The fact is," former IRS Commissioner Charles O. Rossotti once said, "people who make more than $100,000 pay more than 60% of the taxes, and we need to focus there."
If you're making more than $100,000 a year, your risk of an audit is higher. That means it's even more important to keep adequate records to substantiate your deductions.
Recent IRS statistics show a substantial decrease in the percentage of returns audited. Only 1.03% of all returns filed were audited in fiscal 2007. That's more than the 0.98% audited in 2006, but well below the 1.67% audited as recently as 1996. It's simply a question of money and resource allocation. Between 1996 and 2005, the number of tax returns filed jumped from 158 million to 177 million. During the same period, the number of IRS employees declined from 114,000 to 94,000.
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6 ways to keep the IRS at bay - MSN Money