I agree with working on our boats and resisting farming out jobs. In the end, it's probably safer because we come to know the boat and its limitations and ours.
The original poster--Matt--is living aboard in Baltimore winter on a 1972 boat. Rain, ice, slippery docks--the whole romantic brochure and lifestyle.
I don't know how complex a 27 is, but all our boats have 110 outlets from an AC panel (the 38 has five or six). The wires are hidden and they snake through bulkheads. Original panel breakers are 40 years old. The shore power outlet may be original. The power cord may be 30 years old. There may be hidden water intrusion at many points and ancient corrosion. Everything may be fine for another couple of years, but something is more likely ready to fail.
Living aboard is a factor. Our new member is running light and heaters day and night. A typical unexpected event--some burning insulation, a boatfull of smoke, a power cord that flashes off, a cockpit outlet that flares and cooks the fiberglass, can lead not to grave danger but a lot of repair expense.
That's why I argue for at least one inspection by an electrician. He'll give advice. He'll comment on the wiring scheme, note any Previous Owner changes, consider stray current issues. He'll probably want to rewire the whole AC system (which I declined).
That one inspection is good for years, and if you're there ready with questions it's like taking a course in yacht electronics. It will leave you aware of the big issues are, what tools you need, why wire nuts are no good, why the bilge pump should be on the batteries and not the panel, whether the battery charger is safe, what a galvanic isolator is, how anodes work, and so on.
AC is just a lot to feel confident about. I installed a GFCI recently --but what outlet does it go on? And why? What happens on your boat if you have the heater on and then try the new toaster somebody gave you for Christmas?
Mark H, who's no longer active here, was sleeping on his boat in Ventura a couple of years ago when his shore power cord went off like a roman candle. He couldn't believe it happened to him. He was pretty knowledgeable about all this stuff, he said he just never stopped to carefully examine the old power cord that came with his boat. Last summer I stuck a wrench into my DC panel and instantly blew out every instrument on board (Garmin plotter, P70 control head, flux gate compass, all brand new and installed a week before. They all went back to the manufacturer for repair, which took three months. Cause? One measely live wire touched another in a panel under construction. For one microsecond.
For a new owner without a multimeter and schematics, an electrical consultation is what, $200? It can save more than that. And it makes sleeping easier.
Not arguin', just sayin'.