Recommendations for direct vent gas fireplace install in 30 year old home

[cab77]

We have a 30 year old home with a wood frame and siding chimney, brick mantel, and wood burning fireplace (40"x33"). Pics are attached. We plan to replace our roof and siding soon and are considering removing our existing fireplace/chimney and replacing it with a direct vent gas fireplace with a dog house on the side of our house. There is currently a gas line within a few feet of the existing chimney (outdoor grill connection).

My questions:
1. We have received different opinions from contractors -- some say we can replace it without needing to tear up/out the brick mantel, other say it must be completely removed to do it right. Your thoughts?
2. We hope to keep the project under $3000 total. Is that realistic?
3. What brand and model would you recommend?
4. Any other suggestions?

Thanks!
Chad

 

[Heatsource]

You could spend $3k on the unit and venting pretty easily!
add installation and fascia material and you'd be way over 3k

how much heat do you need? a small gas insert could likely be installed for close to 3k