Another option is to estimate value based on potential income and market cap rates, which can give you an investor’s perspective.

It's mostly a joke.I think it did good - the influencer who opines regularly on cap rates, interest rates, the Fed, inflation, and is generally an economist, or even a bit of a philosopher, probably does alright! 

And for reference my sister is dealing with a run down house in Louisiana that has a value of about $95,000 and she shopped multiple policies with multiple insurance companies and the best rate she could get was $2500.

Yes, residential does give me a lower cap rate, but it's more stable. 

This works with any type of appreciating property such as real estate, stocks, etcDepending on the appreciation rate, you can potentially see asset values double every 7-14 years.Likely around 7 years if the appreciation rate is 8%Likely around 14 years if the appreciation rate is 4%If you buy something for $100,000 and it appreciates to $200,000, you can potentially take a loan on the $100,000 appreciation which would not be considered a taxable event.However, be mindful that you are paying interest on the loan and you have to payback the loan but yes, it would not add on to your taxable income.

Do you think SCI can possibly pay a mortgage for ?

Just be sure to factor in interest rates and fees when running your numbers.Know Your Numbers – Accurately estimate rehab costs, holding costs, and selling expenses.

We could make a decent down payment with the 40k, but due to us having little money left over at the end of the month, I'm worried about buying another deal with minimal cash left over after the down payment and not having two mortgages.

Rents, yes 100% I do adjust billing and it is above standard tenancy rates because they are doing it for business revenue. 

These properties cover my mortgage, allow me to save for maintenance/repairs, and are projected to be worth $7–9 million by retirement.