This is going to double as a sort of a business card also.

Perhaps getting a credit card?

And one more question is there any preference between Post cards and yellow letter?

When The Biggest Kid Always Wins The Marbles...Go Play Somewhere Else!

For 3+ families it'd also be good to make sure they have a current green card (issued by the state of New Jersey sort of like a certificate of occupancy renewed every 5 years indicating that the building passes whatever requirements the state imposes). 3 story buildings with 3 units need to have a fire escape, exit signs, self-closing doors, etc.

I just refinanced a rental property last month though, and I chose NOT to take the money out, even though I probably could have gotten about $20K.The reason for this is that I like to be conservative, and I felt - why risk a win?

It is almost always the agent who decides which offer wins.  

I have made up Business card and have started to had them out.

I recently used this company that got me approved for 8 credit cards that gave me a line of credit of $60K...after going to a few guru classes, they told me I could use the credit cards as "investor cards" and use towards my down payment/ closing costs, I quickly realized 1) the credit cards to use for down payment / closing cost is counted as debt for banks when they determine your debt -to -income ratio. 2) They also didn't want me to liquidate the cards in the bank as they didn't want large deposits made.

Try to make it a win for both sides.