Why not just do a smaller batch? You can brew more often. If you get five gallons of good beer, great. If you get five gallons of not so good beer, oh well.
I do three gallon batches and I am fine with that. Might have to scale a recipe here and there but it's not a problem. Your average 20 quart canning kettle, which are easy to find, will easily do a three gallon batch.
I don't have room for a propane burner and tank. Not enough room on the stove for a 6.5 gallon pot. I've tried using two pots, it's a pain also. I settled on three gallon batches and it works for me.
All the Best,
D. White