Both properties have a substantial amount of equity that’s essentially sitting idle.Would it be a good idea to tap into this equity (through a HELOC, cash-out refinance, etc.) to fund future fix-and-flip projects or purchase additional rental properties?

Airdna is a good resource and tool, but I wouldn't rely solely on that platform for data.

Section 8 is best used as a risk mitigation tool for properties in super low income, high crime areas.

Learn about the Net Operating Income (NOI) and Capitalization Rate (Cap Rate)—these are essential to analyzing the potential profitability of a property.Return on Investment (ROI): There are different ways to calculate ROI in real estate, such as looking at your total return after a sale or assessing your rental income versus initial investment.

Use tools like AirDNA or Mashvisor to provide market data on projected rental income and occupancy rates, and make sure your lender works with appraisers familiar with short-term rentals.

Just a follow up question, were you utilizing debt to invest, I have always been taught since a young age to try and not utilize debt (I come from a family of stock market investors, traditional business owners) where debt is not utilized as frequently which I obviously understand debt can be a very powerful tool and utilized in a great way its just something I want to avoid with my investments to an extent any suggestions for investing without debt or as little as possible. 

I believe Pricelabs is offering a pricing strategy and market analysis info more in line with hotels, and that might be a good tool for you to look at.

While every project is unique, the basics he highlighted are essential parts of any construction contract.

Or do you use another tool to search for properties? 

For management, self-managing saves costs and teaches valuable skills, but a property manager is essential for out-of-state properties or scaling your portfolio.