I am self employed. I use a room in my house for an office and a large barn for the business. Can I claim both as home offices? The barn is a free standing structure.

[MaryK4]

Yes, you can deduct expenses for a separate free-standing structure, such as a studio, garage, or barn, if you use it exclusively and regularly for your business. The structure does not have to be your principal place of business or the only place where you meet patients, clients, or customers.  You will have to increase the total square footage of your home accordingly to include the barn.  

See Home Office Deduction for more informaton.

[Tennisfam]

Somewhat similar to the previous question...Does a tennis court count as a separate free-standing structure? This is where I do most of my business and it has related expenses such as court maintenance and landscaping. The court is used 100% for business, we never do anything else on it. 

[LeonardS]

The tennis court is different in the sense that it is not a structure and as such may be a push to claim it using the home office deduction.  However, all the expenses related to its maintenance and upkeep can be deducted as ordinary and necessary business expenses.  You can also deduct property tax and mortgage interest as a percentage of the total property.  An advantage to this method is that if for some reason the tennis court was used for other than business use you will not lose the entire deduction as you would in using the home office deduction due to the loss of exclusive business use.  If you did use the tennis court for nonbusiness purposes, you would have to apportion the expenses deducted between business and nonbusiness use deducting only the portion of the expenses allocated to the business.

[Tennisfam]

How do I deduct mortgage interest and property tax "as a % of the property?" and what if I also have a home office space?

[ThomasM125]

You can't claim a home office deduction for the space in your home if you are able to accomplish the same tasks in the barn. The home office has to be the principal place of business, or a place where you regularly meet with customers.

You could use the square footage of the barn in relation to the square footage of the entire building structure of the property to determine how to allocate common expenses such as mortgage interest and property taxes.

I don't see a problem with depreciating the cost of the tennis court over it's estimated useful life and deducting that as a cost of the tennis business.