I would not use our money for the next project.

Quote from @Scott Scoville: Just finished one of our bigger projects.

If you start a JV in name but do not give your partners proper control and decision-making rights and the deal goes bad you open yourself up to serious consequences which can lead to SEC violations with extremely high fines.Lastly, you can offer the project up to investors who have no voting or control.  

Didn't work out because I still have a project hanging in Upper Chichester (Philadelphia, PA).

Your deal analysis/price, your marketing, or your buyer pool are likely culprits. 

If you decide to revisit STRs, you might want to explore properties where you can project expenses independently, such as using local STR forums or online tools to estimate maintenance, management, and occupancy costs.For networking and strategy-building, you might find local meetups or groups beneficial.

Wholesale, foreclosure, and seller financing can work too, but I’ve noticed that careful analysis and having reliable local contacts often deliver the best results over time.So as you two gear up for your first flip, how are you balancing the potential risk with your long-term goal of buying rentals?

That would set you up and make it easier to scale to another or larger project.

Also, the ability to find good deals with an accurate budget to complete the project up front from some good project managers/general contractors.

Or take the proceeds and do the next project.