We are in the process of buying a second home for our personal use and the use of family and friends (we won’t be renting it out in Vrbo). We have about a million in equity in our current home, and the second home will be roughly 650,000. While we have the means to take a second mortgage, am I wrong to think that we could refinance our first mortgage to fold in this second home, and that, if we did so, it would be grandfathered into the pre-2017 deductions on mortgage interest? That is, we would not be limited to deducting mortgage interest on 750,000 or less?