. - I will ding their credit such that all credit cards and other debt will cost them more.- I will keep their security deposit for funds owed.- I will do my best to garnish future wages until their debt to me is paid in full.This has worked 100% time so far.  

Long term $ can range from 6's-10% range depending on all types of factors - LTV, location, unit count, debt coverage, borrower strength, full doc or lite doc programs, etc..

It has to be an addition.I would double check because maybe the workaround is reinforcing the garage and building above it.We lived in our studio ADU for two years before we moved into the main house.Best thing to do is talk to an experienced lender.

For instance, if there was a total of $250K of debt on those properties that woud leave you with $350K of proceeds to use to purchase $600K of real estate.  

Owning a duplex at 20 is a huge accomplishment, and it’s inspiring to see you’re already planning your next move.From my perspective, real estate investing is a long-term game focused on building equity, paying down debt, and maintaining stability over chasing short-term cash flow.

Trying to decide if we should use a home equity loan for the remodel, do we need to put current home under LLC to help with debt to income ratio & would that affect getting the home equity loan?

Most lenders I've worked with will use the lesser of the current rents or market rents reported by the appraiser when calculating your debt service coverage ratio. 

In my experience, a successful BRRRR typically comes down to two main things: finding a good deal and managing an efficient renovation.

I really like Lease to own option to get into deals without having to take on massive debt.

Any repair issues the new acquisition has you will feel to much greater magnitude due to the property carrying a lot of debt.