2nd letter - after Yellow Letter

[Nick N.]

So I just mailed out the first batch of Yellow Letters. I keep  reading the importance of sending more than 1 letter the the owners. I have 2 questions.

1. What type of letter do you send for the 2nd and 3rd round? Yellow letter again? Typed professional? 

2. What success have you had from continued mailers to them? It's hard to see the benefit from sending to them more than once(but I have read from BP that it works). Please share your success. 

Thanks