I rent too. I fessed up to my landlady when she was round to get something fixed and she said she would ask her insurance people if it would change her policy and I said if it did then we would pay the extra to her. She didn't seem too worried about the safety aspect, I said the floors concrete anyway , that I have a fire extinguisher and that I am careful as I obviously dont want to blow myself or anyone else up. I have mine inside but could put it outside if I needed to. I did read here that firemen wont enter the premises if propane is stored inside and I did mention that to her. I'm not sure if shes checked her insurance yet. There is an insurance company insures flameworkers, again this was found on here, and I mentioned this to my landlady too.
She's very good, fair and did say well it is your business and you need to be able to work!
I think it depends very much on the landlady/landlord. Maybe have a search here and pick out a couple of different points/sides about safety issues and get in touch with the flameworkers ins company, sorry i cant remember or find the name, then give her a kind of report on your findings saying you will obviously do everything you can to keep her house safe. She sounds undecided so you may be be able to move her towards the right decision .
Dont know if any of that helps,
Good luck with it though.