It's a favorable rate, and given the equity you have in your property, you have a good foundation for securing additional funding without compromising this rate.Considering your property is now an investment, and you're looking into financing options for updates, a VA loan could still be a viable path for you, even in your current situation.

Also, after reading RPI by Brandon Turner, I'm aware of multiple strategies, but since I've never actually invested or bought a property yet, I feel like I'm overwhelemd by all the options, and find it hard to get started. 

They offer an option for you to take progress pictures and track your weight as well. 

You will then have a few options with that rent money....you can put it into principal or you can start saving it to purchase yet another property.

If you do, keep the balance low and take advantage of the zero interest balance transfer option on credit cards.

I inherited a house and am currently exploring options to use it to get money to consolidate some of our debt and potentially have money for a multifamily.

If you have 80k cash, you should have many options to invest using rental financing.

Is there another option that the kids should consider?

I am having a designer come up with three options for interior and exterior combinations that are in the same price point.

He will try to justify that joining his program will be your best option, unless you have an unlimited amount of money and time to spend doing the research and learning real estate investing on your own, but the reality is that it does not take much time nor money to learn what he teaches, and even more; it will basically take a dozen of some of the best real estate investing books on Amazon and the time to go through them, subscribing to good sites as this one,  and joining a couple of good REIAs in your area, without having to pay for such expensive and useless mentoring.