Everyone says boating is expensive, to purchase they are expensive but general upkeep and the odd accessory I reckon they are cheaper than 4wding by a long shot. I've owned stacks of boats, each boat I have decked out and probably spent 1-3k max. Think about the 4wd, easily sucking 20k in accessories...
A boat service, $400-700 per year. A 4wd - tyres, etc etc big $$.
4wding is expensive, boating is cheap.
I use Whitworths, Bias and Ovesco.