There are two ways to look at your question. If you mean "logistical" help re: finances, the premier mail handling services have matured into places where crews can have their taxes, documentation paperwork, and routine bills handled easily...at extra cost, of course. The ''standard of care'', as the medical profession likes to say, is to use St. Brendan''s Isle in N Florida.
OTOH if you are asking about financial advising, then cruisers'' needs are no different than any other group, except that a small portion of us may want to deal with arbitrage/foreign currency investing, given that we live off foreign currencies for a period of time. But in general, one person''s "cruising kitty" is another person''s "liquid assets", and one crew''s "long term financial plan" is another crew''s "retirement" or "sabbatical" plan.