Best Yellow Letter format

[Isral Konopa]

So I'm starting my first direct mail campaign.  I've already written some using the most basic yellow letter format.

     Dear [           ]

Hi my name is [         ]

I would like to 

       $Buy$

your house at [          ]

Please call me at

# 123-456-7890

I'm wondering if anyone has any experience with different formats and which have been most successful.  I would appreciate any feedback.

Thanks