Current negotiation from LL Commercial lease Monthly Rent $6000 Security Deposit will be $7000 (based on last month rent of the lease term)Six Month Build Out Period - June 1 to Dec 31, 2024 Lease to start January 1, 2025. 5 year term During the build out period the tenant would pay $3000 per month rent (June 1 to December 31, 2024)The balance of $18,000 from the build out period would be paid back over 12 months at $1500 per month on a separate agreement.

I left that money in HYSA,  deposited it in  retirement accounts or brokerage accounts (mostly stocks, index funds, a few REITs) 

or have the current seller provide said info. with proof of payment and or renters insurance, turnover of security deposit & first months rent which my attorney will also be collecting, With it being such a quick turn-around with their current lease expiring I want to have as much lined up as I can and be the most prepared I possibly can.Currently Still in the process of bulletproofing the new lease along with the operating and reserves accounts & setting up account/property management software.

Do I have to tell him or can I just deduct the removal and replacement fees from his security deposit?  

I have a "keep me out trouble" deposit with an eviction attorney.

That loan will have some bank hand-holding that people dislike (annual reporting requirements for the first few years, all rent checks must get deposited into an account at that specific bank so they can see it coming in and have an automatic "early warning signal" if they drop off, etc), but hey in their case I'd say it wasn't unwarranted, their only track record is that of mismanaging after all. 

Recently, I've encountered startups and companies offering quick EMD financing at high interest rates (around 3-5% per month). Are borrowers who utilize these funds typically involved in flipping properties? This seem...

No return of deposit until both parties move out, they need to work things out themselves.  

You may qualify by using bank statement program as that program uses all your business deposits to calculate your income.

On my side it shows paid in full until it’s time to make the deposit.