Yes,
the jet ski can be written off as a business expense, but on your 2016 return after
you have started your business instead of the 2015.
Even though it may have been purchased for the
business you plan to start in 2016, you will need to wait to include it as part
of your tax return for 2016. It cannot
be considered to be a startup cost for the business. It would be considered a business asset or
equipment that will be depreciated.
When you are working through the income and expenses
section of the tax return for the business in 2016, it will not matter that the
jet ski was purchased in 2015. It will
have been placed in service for the business in 2016.
Please take a look at the
article Startup
Business Tax Tips for more information about
startup costs and some other tips.