I was able to qualify for about $95k in 0% business credit cards (for 12 months), I then liquidated the cash and used a portion of that to obtain the hard money loan that covered the balance of the purchase cost.

Should get a lower interest rate on your loan since these are liquid assets. 

Many investors use this “infinite leverage” approach to maximize liquidity and tax efficiency.

Structural engineer is definitely first step as Mason mentioned.It totally depends on liquidity, risk tolerance and time.

A cash-out refinance on one rental could provide liquidity while keeping rates reasonable.

Some sales contract's don't limit the seller to retaining the $5k EMD, they can also seek liquidated damages in addition.

Tax StrategyWhile liquidating the brokerage account may trigger capital gains taxes, strategies like staggered withdrawals or tax-loss harvesting can help minimize the impact.

Recently, I sold my position in a company due to an acquisition, which liquidated $750,000.

Each investor would still choose their preferred properties and the corporation would liquidate enough to pay taxes.

All that said, depending on the size of your RMDs, liquidity needs, and total income, you may consider making deductible contributions to your own IRA ($7k limit, $8k if above 50).