If I am aiming for the national tenant, what kind of TI per sqft shall I expect, how much security deposit I shall collect and  how many month of rent I shall ask tenant to pay advance to execute the lease (1st and last month of rent or more)?

You can get RE taxes from town assessor.

I’ve been doing BRRRRs in Memphis and Detroit since late 2020 and now have 9 doors across those markets. 100k with the right deals can allow you to scale to about 8 or so doors that all cash flow (after taxes, insurance, property management, mortgage) about 400-500/month each.

In a nutshell, I buy secured debt ( real estate note secured by a mortgage or trust deed)at a discount from a lender.

Market rent for each is 1950-2100 (the 1600 tenant was there when I bought it and super low rent but great tenants so i made a plan with them to raise it to market over the next three years as the jump would be way to much all at once). mortgage currently with insurance and taxes escrowed is 2100.I have a really low rate which makes this decision hard but the equity would help me fund the next 2-3 deals and enable me to start scaling faster

A tenant destroyed a garbage disposal with a shot glass- the next thing in my lease was tenant payment for repairs not coming out of security deposit and specific terms for hourly labor charges. 

As a landlord with numerous Section 8 tenants, I can attest that participating in the program can be a great way to secure reliable rental income.

What’s the best recommendation for newbie into finding wholesale buyers while securing deals?

This is for tenant occupied or turnkey properties that I want to cashflow, not hold for losses, deductions, or depreciation to offset taxes.

So, after paying off the mortgage,  would net $58k (and wouldn't pay capital gains taxes as I have so many losses from previous years).