After the Brexit, doing Business in Europe will certainly be more complex.
Travel Visas, VAT regulations and new Import & Export rules will probably have an impact on your day-to-day operations.
Through investment in Real-Estate or the acquisition of (or investment in) a Spanish Company you can easily obtain this special investor visa in Spain.
This implies you can do business in Spain and from Spain to the rest of Europe.
You can live in the UK, and visit Spain and the rest of Europe as many times as you want. You can even reside permanently in Spain if you wish to do so with your family.