do you know how you will fund the acquisition? 

At the end of the day, I understand you want to keep a 4.5 or 2.5% mortgage however if you come to find out that by accessing those funds via a second mortage, your overall payments would be higher, it actually might make sense to refinance and use those funds to invest. 

I have considered trying find deals and bring them to current investors to learn but not sure on how the Self-Storage Funds do Lead-Gen.. any thoughts or insight you can share with a fellow CPA would be much appreciated.

Right now we have enough for a 25% downpayment on 2 $300k properties, and I'm just trying to find the best way to allocate those funds.  

Invest the $550,000 in a mutual fund such as S&P 500 or VTSAX with a 10-year history average annual return of 12% 2.

Investing with personal funds creates a taxable event when you liquidate the asset.

It's great you already have the location, price range, and funding source! 

It’s crucial to stay disciplined here, as overspending on land can limit the funds available for construction and other expenses.Development Scale: I’d recommend avoiding developments in the range of 4-50 units unless you have a very specific reason.

I put my money where it’s going to perform best, either in real estate or my brokerage account in the form of an S&P 500 index fund.

I would also put part of it in a debt fund.