Hi Michelle
I'm one of the few British ex-pats living in Sousse. We are in the minority. Most foreigners are French, Belgian, Italian, Danish and Libyan and almost every other nationality as well! Recently met a few Irish. Local authorities are overwhelmed with applications for residency (carte sejour).
If you intend to start a small catering business go for Sousse / Hammamet alhough Hammamet is almost dead in winter as is Mahdia. Not sure about Monastir but having been there seversl times out of season all the restaurants were empty.
I'm not going to dampen your hopes but if you come to settle here think very carefully!! This us NOT Europe and doesn't function like Europe. Unless you have trustworthy local tri-lingual contacts you will, like all of us waste months and months going round in circles getting no where. The problem is this is a society where corruption goes unchecked. Also even officials do not know or cannot articulate their own laws. Believe me I know after countless visits to the Doane, Bureau des Estrangers and lawyers!! Beaurocracy is dreadful..you must be patient beyond belief...
Language ..English is the 3rd or to some, 4th language here and while some peoole in tourist areas speak English most only speak arabic or french ...take lessons beforehand. I go to a great language school in Sousse ..it's been a Godsend. All official documentation is only in french or arabic or you need to get it translated.
Finally... don't share your business plans with anyone or trust anyone with your money. Not all Tunisians are bad (I've got a couple of super Tunisian pals) but tourist areas are places where the unscupulous gather to scam tbe tourist or ex-pat. Locally known as "beezness".
Also choose your bank here wisely...most are a total shambles but interest rates on deposits better than what you get back home.
When you get over this, learn and appreciate the culture differences and turn a blind eye to the dirt and lack of certain stuff we're used to back home, the pace of life is slower and much less stressful (aside from Ramadan and driving) better, healthier climate, doctors/dentists/opticians/cosmetic surgeons are some of the best in tbe world, cost of living 1/3 of UK with cheap fuel and utilities.
You have to be "au fait" with insects as they are a plenty in summer witb temperatures in tbe mid 40s. Ramadan is hell on earth in Sousse if you make a move do it before or after...
Hope that helps. Bonne chance!
Carole