I had a-lot of luck with my tent from Walmart for $ 25.00. Its reusable too, just dump out the shavings and hose it down. Let it dry in the sun and fold it back up.
The downside is you need somewhere secure to set it up as it really isn’t predator proof at all.
I had it set up in my living room with a tarp under it ( I have porcelain tile floors so this was fine.) I felt it was to cold for them at the time out in the garage plus I had a broken ankle so living room it was lol.
Fast forward to this batch of babies. I set up the tent in my garage and moved Brownie and her chicks shortly after they hatched into the tent. There they stayed until they were 3 weeks old at which point I transitioned them into the coop.
The tent I found was just the cheapest one available and has a footprint of 7ft by 7ft. It’s HUGE for a brooder lol.
Perhaps this could work for you?
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