Depending on what type of underwriting method a Mortgage Broker found most suitable for your scenario + your credit score, you could get slightly lower interest rate although 6% is a good number to plug in to be conservative.  

If you have the down payment and just need someone's credit let me know.   

Check the local banks and credit unions. 25 year amortization is more typical for a loan that size so I would make sure 30 yr am is accurate.

My experience with commercial loans in NJ, has been no personal guarantee, because the lender looks mostly at the income potential of the property vs. the business (LLC) or even the owners personal credit/assets...

Let's say that I want to get a mortgage credit certificate (MCC) on a home that I am going to live in. 

You must inform and provide the appraiser with all the rehab/reno improvements that you plan to do to the property, remember the value will be the ARV after ALL rehab/reno is complete.

Shop around to local/regional banks and credit unions.

I had a similar situation; after calling most major banks/lenders, and getting "no actuary will every approve that," I was able to work it out with a local Credit Union. 

We thought about using credit cards to fund the renovations but don’t want to risk damaging our credit score to do so.

When you buy real estate you don’t buy the “structures”...... the land is what you’re buying and any permanent structures/improvements are simply included.You say both houses are on one “plat”.....does that mean both houses are on the same property tax I’d no., or are are there separate legal descriptions/lot no.s?