An extensive checklist of issues to deal with post-Brexit means a potentially very big expense bill for those clients looking to retire to an EU country, effectively making such a move "the preserve of the rich" according to international advisory firm Blevins Franks.
Delays in the systems and securing the right documentation may mean having to apply multiple times, while further costs mount up if the documents have to be translated and an immigration specialist is employed.
Clients also have to demonstrate that they have sufficient income to support their family without being a burden on the state. In Spain, for example, they must prove a minimum annual income of €27,115 plus €6,778 for each additional family member.
One of the EU Golden Visa applications if not done properly could cost €40,000 in lost fees."
Jason Porter, director of Blevins Franks and head of the company's European Emigration Advisory Service, said: "All of this means that this is the preserve of the above-average wealthy.
"Get the residency application wrong and in most cases it is void and the application fee is lost. Not only will they have to start the process again from scratch, but they will have to come up with more cash for a new application."
He added: "Golden Visas allow Britons to gain residency rights in many EU countries in exchange for investing a substantial sum in local property or investing some other way in the economy.
"They certainly would not want to try to obtain a Golden Visa on their own as they average €5,000-€6,000 each and an application that has to be resubmitted would cost €500 every time.
"One of the EU Golden Visa applications if not done properly could cost €40,000 in lost fees," said Porter.