We moved into a new house, and it's old. The fireplace is collapsing in on itself. We have a quote for a temporary fix for $800 or a complete rebuild for $3500. It's only the back wall of the fireplace that's collapsing. Is it possible to just cover the inside of the fire box with steel, creating a metal firebox inside? That seems a whole lot easier and cheaper. Is there something I'm missing? $3500 seems like a lot of money for the amount of work needing to be done.

I will ask

What does this mean it is falling in and just the back

Is it a fullpiexe or actual mortar and firebricks

If a fullpiece Then order it on line and donyourself

I can give advice if need be

If firebrick you can do that yourself also

Follow advice above if you are handy. If you aren't, You aren't missing anything. You are paying for a skilled tradesman to do skilled work. We use our fireplace daily during the winter, I'd rebuild everything I thought needed to be built to make it safe to burn a fire in. I hate having things that don't work. 3500 seems high but I don't know what they are doing, I'm a speculative Mason and not an operative one. There is also always more than one way to skin a cat, so you'd be well served having a few professional eyes on it along with some additional ideas and estimates. Masonry is a craft and this is also a safety concern. Personally, I'd find small mom and pop shops that have been doing this for years rather than some chain that hires the guys from the local Home Depot Hope Tree and charges out the nose for them.

$3500 seems fair for a NEW fireplace, chimney, hearth all wood burning
so if that includes tearing down, OK. I don't about read any salvaging but that can go either way on savings.

Temporary fix w/o details seems fishy to me with all the house/chimney fires reported this time of year.

Talk to your mason about tear down, then DirectVent fireplace options (not wood burning) that may save money, burn gas/propane, no ashes, no termites/snakes in wood pile.

Costs
https://rebrand.ly/wvs2m70
Life - I disagree - if well done (e.g. Master Mason), should easily be twice the life noted below
https://rebrand.ly/8jsmlr6

Let us know what turned out best for you ....

Still looking into this. It's an original fireplace from 1978. Brick and mortar. The backside is collapsing in toward the house. The bricks are broken in the middle.

I am pursuing a different route too. I know a metalsmith who is pretty confident he can make something out of steel that would keep the bricks in place and serve as my fireplace. He says it would be much cheaper since I would only pay for materials in that scenario. He's investigating on whether this is a good/safe idea.

Any additional thoughts to add? Not crazy about a $3500 pricetag to rebuild it when there may be other options.