How do you chose an allergy friendly accommodation?
When I'm planning a trip I like to choose accommodation that allow me to make my own meals in case I have trouble finding restaurants where I can comfortably eat. My go-to lately has been AirBnB apartments because of the private kitchens. In the past when I've stayed at hostels, I've made sure to read a lot of reviews to learn about the kitchen space to see if I would be comfortable using their communal space to cook. When I have chosen to cook in hostels, I have just made sure to thoroughly clean the space and items before use.
I've had 90% success saying at AirBnb's with food allergies. I've had a few experiences where I stayed in a shared house with a family who cooks a lot of ethnic cuisine. This made me a bit uncomfortable using their kitchen and dishes. In those cases I've often dined out more than stayed in - which kind of defeats the purpose. I recommend looking at renting full places instead of just a room as you'll have a better chance of getting a kitchen designated for guests only.