I was wondering what the environment is like these days with finding off market deals and foreclosures (non existent because of eviction moratoriums??)

Generally how much buffer time a landlord needs after an existing tenant moves out and before a new tenant moves in? 

Not sure if that specific program still exists but it came about due to Covid-19.

You will also want to explore the great tax benefits available right now with cost segregation on any new property or your existing property.

You would need 20% down though with Conventional.Otherwise, you could refinance your existing property to an investment property Conventional loan, which if it's a 2-4 unit property, you would need 25% equity (75% LTV max). 

BRRRR is the most efficient way to start/grow a small portfolio, but impatience expressed financially is debt, so you can't be shy about racking up mortgages.Once you get going with BRRRR you will get to a point fairly rapidly where your personal income streams that exist now could not cover your debt service payments for your investment properties and how far past that point you are willing to go will determine your growth potential.

The first question I would ask myself is do I want to keep the existing tenants?

I purchased a rental property in 2019 with 20% down conventional loan. I have renovated it slightly and have had a good renter in the property for over a year. I recently have been learning the BRRRR strategy and had ...

it might be useful to alter or renew existing lease. he had good credit history ,so I hope he will try to keep it clean and move out.

It basically was a wealth transfer to owners of existing OZ property.