Mortgate interest deductions only apply if you itemize.
Mortgage deduction may be deductible. I'm not current, but in the past there was a limit on how many different things could be included. Example, you might have a home mortgage, home equity loan, vacation cabin somewhere, RV loan, Boat loan, one or more Timeshare payments, all at one time. You could not deduct the interest payments for all of them.
I think the limit was two, so a primary mortgage plus one other.
You need to verify with your tax advisor or the IRS.
Unless it's changed, the rule for RV or boat interest deductions were only allowed if the RV or boat was fully self contained, meaning it had sleeping, cooking, and bathroom facilities.