What do you qualify as a proof of funds?

[David Cheng]

Currently have a listed 4-plex for sale, 100% occupied. As a screening tool, I ask for proof of funds before we bother a tenant and show the property. 

To me, any liquidity qualifies: bank letters, bank statements, stocks in an investment account that covers down payment, etc.

Today, I got a letter from a hard money lender saying the buyer is approved for 1/2 the listing price of the property. No proof of liquidity.

When I asked for any proof of liquidity, the realtor says they are not interested in jumping through hoops and called me a jackass.

Is this how business is done now?