I really don’t want to get that risky with the first one but I am working full time to cover those “extras”

People will start to ask if you need some extra cash to do the deals.

Because either way any extra money that you take out from the cash out refi you still have to pay back, correct?

if you share a home with your parents and wife, your income (and your wife's) should be able to go a bit further than if you were single or the two of your lived on your own.You were able to save enough money for a down payment on your current home, so do a quick check of your finances and see if you can earn extra income or cut expenses to save for a rental. 

Why wouldn't you want to make 3x for a little extra headache....?

New loan - ~70-80% of the ARV (126k in your example - paying yourself back the 100k, plus 26k extra)Closing costs (generally rolled into new loan) - lets say 4k for example (you should shop around to see best option)Total loan amount that you are paying back monthly - 130k (plus insurance, property tax)Dont forget about the seasoning period though!

Again, the extra money spent on the membrane and the stickier/harder mortar ends up paying off here.The only realistic exception to this advice would be if you have big cracks all over this concrete slab -- but if you had anything sizable enough to worry about, you probably would have mentioned it already.

We are not sure how to go about the extra bedroom since it was already built and its part of the house.

(Many can) If you could switch to VA it would be better for you but the seller may have an extra cost or two- ask your agent.

I can take those 99 extra hours and invest them in more research, etc.