How much equity is there in this property, or is it paid off?

That would likely be the easiest.How much equity do you have in your current property?

I feel like I can't get a true picture of my investments if I can't calculate what I'm doing to my equity and my increase in expenses for closing costs if I can't factor in the cash-out refi's - unless I don't need to. 

I can definitely tell you there's still a lot of positive cash flowing and 1% rule deals and you get amazing appreciation.

Or go the route of buying a single family, doing some upgrades, live in it for at least 12 months and a day and then pull out some equity to go buy another and rent that one out.

If the paint does test positive, you'll need to follow regulated procedures to clean it up (or contract it out).  

Where is the single family property located, how much equity do you have built into it, etc.? 

At 75% LTV you avoid PMI and have significant equity in the property which leaves you with options.

So, if there is zero equity, you can put all house into a single LLC.

If you decide to do a value add or build you can expect a 6-10% cash on cash return on 30A with a 35-40% equity position in the value of the property.