Time: A Couple of Hours
Skill Level: Beginners
Bravery Level: 1 Star
Now here is an item I highly recommend.  Mrs. Mumphy gave me a dual voltage refrigerator for use at the office.  It very quickly found a birth on the Christopher-JIn.  The one she got me came from The Sharper Image.  Depending on how much room you have and what your desires are they also carry a wine chiller.  You can also get a freg by Koolatron at Amazon. The Koolatron (unit runs about $120 but you'll have to buy an adapter to run it on AC for another $16.  I haven't tried the Koolatron but I'm sure it would do the job.  They offer several different configurations.  I also understand that Target carries some of their products as well.
The mission is simple.  Keep a small quantity of beverages and water nice and cool and ready to go when you are ready to set sail.  One important modification I made this year was to add a tray under refrigerator.  The cooling element tends to frost up a
bit and then slowly melts when the power is off, like when you are underway, which can lead to water leaking out the bottom of the door.  Since my frig sets on the galley side cushions, they would get wet.  I built a plywood tray with a raised lip and that did the job.  You can mop up the water or let it evaporate.  I tend not to run the frig while sailing to keep the draw on the house battery down but I think I'll try it this summer to see how bad it really is.  I'll keep you posted.
What I did on the Christopher was to run an accessory outlet over to the forward side of the galley bench as well as a 120 volt extension cord.  I snaked both these cables along the inside edge of the teak trim of the shelf and then across the top of the opening for the sliding galley.  I kept the cables up and out of the way with a couple of cable clamps screwed to the top side of the lip.  You have to be a bit of a contortionist but it's worth the effort.  Once you get a cable or two neatly in place it's easy to add additional cable runs by tie wrapping onto the first sets of cables.
The bottom line:  Take a little extra time with all of your initial cable runs, establishing a clean, neat cable path, then add to it as your needs grow.
I always run the frig on AC shore power unless I'm underway.  These units draw quite a bit of power so be careful running them on your house battery.
Also the unit shown here will automatically switch between AC power and DC power.  If AC is available then the unit runs on that.  If shore power is disconnected then the unit automatically switches over to DC power.