Those make for nice heating stoves as well as decorative pieces but yours appears to be in “rough” shape as far as appearances go.
As a heating stove it would work fine as long as the grates in it are in good shape. So, as an emergency heating device in case of power outages or just to “warm-up” a cold garage or outbuilding, or to burn paper/wood trash in it ought to be worth $50 to $100.
But what it needs is a good “wire” brushing and a liberal coating of “Stove Black”, NOT black paint, and then rubbed down with a soft cloth.
That won’t help the nickel “trim” on it but it won’t hurt it either. To really make it “shine” all those “trim” pieces that were originally nickel “plated” needs to be removed, re-plated and re-installed and then you would have a thing of beauty.
But unless you are going to keep it for your own use the co$t of that “re-plating” might exceed it’s selling value.