Very Long Term Storage...

I have a friend who is moving away for about 4-5 years and thus won't be using his Tohatsu 6HP SailPro.

He asked me for some long term storage advice...

Other than the usual and customary winterization (change lower unit,etc), i am thinking he should: run ethanol free fuel thru system to reduce any ethanol impact, tape over the carb air intake, remove plug and tape over the hole, tape over exhaust port, maybe some oil in cylinder..? Though not sure with 4 stroke, spray with Boeshield, and store in his basement...any other precautions?

Then again he can just do his normal routine and when he gets back do a carb cleaning and impeller change..?

fog engine,pull plug and fog inside of cylinder,replace plug,drain down fuel system,pull drain plug on carb,spray under cowl with wd40 or equivalent to prevent corrosion,would not be a bad idea to wash exterior of motor,dry and put a coat of wax on it

Yes. Change crankcase and LU fluids, completely drain entire fuel system (including carb, lines, and pump), fog intake and cylinder.
You can run the motor on 2-stroke fuel for a few minutes before draining the fuel system, to get a preservative oil residue inside the pump, valve, and carb... reducing corrosion.
A wash and wax wouldn't hurt.