@Julie1660
Maybe search on Airbnb in your region and look for long term stay accomodations with pets allowed (pets allowed filter can be set, also max. pricelevel can be set). If found something suitable, you can contact the host via "contact host" textlink and ask questions. Please note on Airbnb the person who is booking must be the person who staying (no 3rd party bookings allowed, unless supported by Airbnb upfront)
I found 4 accomodations from GBP 433,- to 884,- a month when searching for Somerset UK, 3 months from 1 july onwards, pets allowed, pricelevel max. GBP 1000,-
Best regards,
Emiel