@AJ Harris you may have $30k in equity but you likely will only be able to get refinance at 75% LTV which would be about $86K, so you would only be left with $6K after paying the original mortgage off. You'd probably be better off helping your mom sell the house, avoiding capital gains, splitting the profit with her then using that money towards a down payment for the next property. To be honest it doesn't sound like there is enough equity in this house to do to much with it. that doesn't mean you can't achieve retirement by age 40. Give us the answers to the questions that @Michael Plante asked and we could better help.
A simple path to Financial freedom is: Save 50% of your income, use your savings to invest in a multifamily property that cashflows and can allow you to force appreciation by rehabbing it. use the forced appreciation to cash-out refinance. Use the cash to by another multifamily. repeat. AKA: Buy, Rehab, Rent, Refinance, Repeat. BRRRR. follow this model and in 10 years from now you can realistically own 20 units, cash flowing a total of $5,000 per month.