Cost involved in ending a SAS versus visa work permit for business owners tax based in UK

My husband and I bought a company in July 2017 SAS which we run as a seasonal business in France as it deals in plants open March-June, then sept-nov. We have a separate ltd company in the UK, nothing to do with plants and not linked in anyway to the French company. With the new laws after Brexit, we are concerned about the 90/180 day rule and how we would feasibly be able to run our French company if we are only able to physically spend 90 days at a time in Europe with an imposed 90 days back in the UK in between.

Having calculated the costs and charges involved in income tax and social charges in France, we have worked out it would cost us quite a bit more if we were to declare our revenue in France (salary and dividends made in the UK) if we choose to become french residents. We think therefore that we have no option but to remain UK tax residents and potentially end our French business. We invested around 90 000 for the purchase less than 2 yrs ago.

Could you tell me what costs would be involved in ending our SAS please, if we are left with no alternative or perhaps who we need to contact and how to go about a possible work visa allowing us to work for longer in France although without salary, without becoming French tax resident.

At the moment we do not draw any salary or dividend from the French company instead we employ two seasonal workers to support us in the workload when we are working for the company in France and their salaries are paid instead of anything for us.