Hello I'm posting here because I would like to make a more permanent forge. I'm currently using a brake drum lawnmower forge and would like to make something I can use in my building during the winter months below you will see pictures of my shop and the forge designs I like most. 
this is a link to the coal forge I was interested in
https://www.youtube.com/watch?v=Bn1qbC3EbPM
this is a link to the propane forge and a link to the burner I would be making with the help of a gas fitter.
http://www.zoellerforge.com/simplegasforge.html
http://www.instructables.com/id/how-to-build-a-gas-forge-burner/?ALLSTEPS
Also if gas is very expensive I would like to know due to the fact I have not used it for forging nor do i know how long a 20-100lb tank would last me. If someone has experience with gas forges and knows roughly how long the tanks should last me I would appreciate this very much.
Thank you to anyone that replies.
These are the photos of my shop.
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If anyone knows of a source where I can get an actual firepot that would be a great help or something that I could use other then a brake drum

Centaur Forge  and Pieh Tools sell fire pots, tuyres and full forges. As far as "safety", from what I see from all that sunlight streaming thru the walls, good ventilation shouldn't be an issue as long as the forge is installed properly. With a coal forge that would mean a hood and flue. Gas, simply common sense.

Good Morning,

I have two forges made in Duncan, B.C. by Lorne Bakker. Mightyforge dot com. We used his forges when we hosted CanIRON VI in 2007. They are simple and very hot if you wish. Contact Lorne, he has a sale advertised locally.

When Kwantlen College in Cloverdale, B.C. built their new campus, they switched to the Mighty Forge for their Farrier Program. No more Coal/Coke. When Hank saw the forges at CanIRON VI, he said "That's some Forge". For that much to come out of his old Cowboy/Teacher mouth, that is a remarkable statement.

Neil

Thank you for the source on fire pots and over all if anyone has an idea judging from both projects what does someone think would cost more to make the gas or the coal forge 
Thanks.

A good cast iron fire pot is running a bit more than double the cost of the gas forges I have built and used.

Good Morning,

The propane forge from Lorne is ready to go to work in one minute. Propane costs are not expensive. Approx. 10hours from a 20lbs. bottle

Coal costs plus the Environment Fee that we had to pay, the last time we bought 40 Tonne was about $5,500 with the trucking. You may have room in your Barn to store Coal, but not for a Dump Truck to dump it. Bagged Coal is available from Home Hardware Stores. I know OABA was getting Coke from Stelco, I don't know if that is still available, check with John Newman. John also makes the best Fire-pot, that is available from anywhere. We have 4 in our Shop.

Another sunny day above Mother Earth, YES!!!!!

Neil

if you're good at scrounging and have a decent amount of tools on hand already you can make forges or relatively cheap. My gas forge, if you include the fire brick I already had cost me about $100 to build using a Frosty T burner. and that was using all new fittings, regulator, valve, and scrounging the fire bricks out of my smoker which isn't being used at the moment.  

If you're looking to build a coal forge with a hood and flue, and you're on a budget, you're going to have to become very good at scrounging because that's a VERY tall roof line. and chimney stack isn't cheap. 

Have you been running your drum forge in the barn already? Based on the openings, I would think a calm breeze would be enough to make it seem like you're outside in that space.

what kind of tools do you have at your disposal? do you have a welder? Access to the right tools is a big help in keeping costs down.