(and certainly not all the extra interest that accrued at the higher default interest rate. )Question : Do we, as investors, then get to claim a tax deduction or write-off for all the interest - including the default interest - that was not paid?

All expenses are paid by the IRA and all income accrues back to the IRA tax free.  

I could just slap the immediate costs on my 10k limit CC and start the process of another fixed rate advance to pay off the CC before any interest is accrued.

Its Highly likely the borrower will go into bankruptcy prior to letting the property go. so, what does this do. the first keep accruing default interest and expenses that comes in front of you. you have to hire an attorney more money out of pocket and if your IRA just happens to not have enough money in it for expenses this jeopardizes your IRA. 

Is it accruing interest? 

that’s if he can get financing with all the student loans he’s accrued. im a tradesman.. 0 college, $0 debt.

I'm sure there will be an aha moment when you haven't visited the property, called your PM, or even thought about the property for months and yet you still keep accruing more $$ in your bank!

I had one client who didnt heed our advice on avoiding Rocket Mortgage, mentioned that they ran their business out of the home, and accrued and addition $10,000 in fees/points on the loan.

However, there is something to be said for holding the property and accruing more equity and having even more options down the road.

The way I see it, the major pros of home-ownership while renting rooms (house-hacking) are 1) that you are accruing equity in a home with a very high value due to your location, 2) you reduce your housing expense, because you have to live somewhere anyway, and 3) your home will likely appreciate greatly over the course of your ownership of the property.