I'm not trying to be negative, but realistic. I think your going to have a issue trying to find a trailer without chemical issues. There are many chemicals and glues used in the manufacturing of these. Every time you turn on the furnace and heat things up gasses and smells can be released. Something gets wet or moisture collects someplace could cause a release of something into the air ( water getting to the wall or particle board).
We've owned 7 rigs and everyone had distinct chemical smells that never completely went away. I hated when having to turn on the heat, so we used electric oil filled heaters. I have allergies and there have been many rigs I couldn't even walk in when looking as they made my throat and nose close up from just sitting in the summer heat.
I don't know the extent of your health issue, but if it's that bad it isn't going to be easy for you.
