How do we report mortgage interest for a 2nd home on my camper on Sch A Line b. I don't have a 1098 and it's not a seller financed loan.

Schedule A just reports one number. Everything else is worksheets behind the scenes. If you have a qualifying second home, you can deduct the mortgage interest and the easiest way is to simply add  a fake 1098.

Enter the second home, 

enter the interest information, 

yes secured - if it is, 

not heloc, etc.

 

Reference:

IRS | Second Home

IRS | Home Mortgage Interest

 

for the interest to be deductible that camper must have cooking, sleeping and toilet facilities