Answer:
I start new then become old. Start clean but be one dirty. I usually start big then become little.
My first is a heir; My second's a snare; my whole is the offspring of fancy; which I sent out of play upon Valentine's day As a token of love to my Nancy.
What is always in front of you but can't be seen?
A man shaves several times a day, yet he still has a beard. Who is this man?
I shoot but never kills
In your fire you hear me scream! Creaking and whining yet I am dead before you lay me in your hearth.