i usually do my yearly service in the fall since i dont winter fish much lately. change oil, change gear oil, check fuel filter, if its time for new plugs change them, mercury usually recommends fogging the cylinders but since mine is only up until february i dont worry about it. on my yamahas i always did them. check the prop seal for line and damage. make sure thr engine is all the way down to drain any water out. check the hydraulic fluid and grease of tyengrease points. put 15 oz of mercury quicksilver fuel treatment in the fuel tank and top it all the way off with non-ethanol gas.
ill also check the prop on the troller for line and any water intrusion into the foot. also check for electrolysis corrosion.
you can take the batteries home just tape up the battery cable bundles and label them. make sure you dont reverse polarity when you connect them back.
with all this done, all you have to do come spring fishing to re-install the batteries and you are ready.
nice boat by the way. if its a 2010 its kind of a unicorn with that year being the only year they rated it a 90hp transom on a 175. i looked for one in descent shape but never could find one.