Oh dear. Interesting times for sure.
They'll need to crank it and make some serious money immediately. They have a big payroll of "experts" on hand! Maybe these big firms will do some pro-bono for the prestige. No doubt it'll all be squirreled away in a dodgy tax haven.
I'm thinking upmarket alcohol a-la George Clooney (you know, owner and face of the brand and then cash in by selling the company) and day-to-day expenses met by the after dinner speech circuit a-la Tones and Barack. A bit of publishing / documentary / self-advertisement. Some vanity stuff about elephants in Africa and empowering the peasant girls of Canada. All carefully orchestrated with press releases and photos and motivational quotes. Too bad they won't have access to the royal diary so their various projects can be impeccably timed.
I really wish the press would boycott it all, but that won't happen alas.
They're already entering murky waters with the free mansion in Canada. The press will find out all about their host and gleefully publish any details that are less than salubrious. Exhibit A of warning should be Uncle Andy. I wouldn't be surprised if some elements of the British media establish a dedicated "Hazza & Megs Dirt Digging Department". All that hard-earnt independence money ending up in Harvey Specter's pocket. Oh, my.
I think that Mrs Mountbatten-Windsor is going to be a hard task master to poor old misunderstood and so-put-upon Mr M-W. I actually believe that he genuinely wanted to leave and she's just giving him the moral support / kick up the backside to put his desires into motion. It's not like he has the gumption / intelligence to do it on his own. She'll probably tire of his dimness and kick him to the kerb in 5 years time.
Further on, I think that America will still sustain them because they don't understand / care about the subtleties of royalty and royal-ness. The Sussexes will happily go along provided they see the cash.
Everyone's a winner.
Except, perhaps, their little boy.