You can deduct the interest that way...not really the cost.

The fed has been tightening the tax write off's in the last several years and I suggest that if you do so, you have legitimate and detailed records on why the trip was a business expense (who, what, and why). It needs to be semi-believable because they will expect the detailed records and something to believe in should you get audited. Also, you can only show a business loss for three continuous years. Bonnie works too hard and I've never been able to show a loss though I do record some regatta trips as business trips but only when I can show that we donated the t-shirt design, made a product toward the regatta (shirts, awards), or legitimately had a purpose to discuss business with someone in the area.