What was the most surprising thing you learned when transitioning?

While you might find a lender offering low down payment options, you'll still need cash reserves for repairs, maintenance, emergency fund (ideally 3-6 months of expenses), etc.

Wait a few more years and I would not be surprised if every SFH can be converted to a quad.  

The overall LTV (including all 3 mortgages) will be key and your selling point will need to be that the 2nd mortgage ($8k) will burn off in 2.5 years (based on your surprise that it was even out there, I'd recommend that you follow up in 2.5 years and ensure that it's been satisified, so that it doesn't surprise you again in the future).Does the $8k grant vest over the 5 years? 

, takes the edge of the emergency and buys us time to get a contractor out without having to pay for emergency hour services.

Usually a pattern will emerge on a 'normal' deal in your area.

In my Longmont flip, we made sure to account for worst-case scenarios upfront so there were no surprises later.

You'd be surprised how many leads they get that they just don't want, or have time, to work with.Good luck!

I am also surprised that a couple could have credit scores 100 points apart. 

The seller should not be expecting you to be the buyer, or surprised when you aren’t.