Re: New sailing family + new (old) boat = OMG
Rigging the boat is kind of a toss up. I have done it both ways, but I defiantly wouldn't consider hooking up batteries. I would tell the broker that if the electrical system doesn't start, or the engine won't start when I arrive I will assume there is something wrong with it, and adjust my offering price to reflect replacement.
An accepted offer is just the beginning of the negotiations on a new (to you) boat. I have never (including professionally maintained ones) seen a boat that passed my sea trial and inspection. The fun part is going back to the broker with a list of the unexpected and negotiating for who is going to accept which costs.
Typically those things that reflect poor or ignored maintenance will be the sellers, while those things that are age related are the buyers (particularly if they were disclosed, like engine ours). Until you get the survey report and sea trial report back though you really don't know what you will have to do to get her up to snuff.
Remember a sea trial isn't a pleasure cruise. It is your last chance to find everything wrong with the boat before you spend a lot of money making it yours.
Just a short list of things found during sea trial that resulted in reduced prices
Engine wouldn't start
Generator was rusted out
Sails were mildewed and scuzzy
Mast pumped way to much
Shorter mast than spec (a 100' tape measure is a good thing)
Entire electrical system was non-operational...Took 5k off the price, turned out to be a fuse
roller furler wouldn't roll
Steering was very tight (bent rudder shaft as it turned out)
Steering was too loose (broken rudder straps)
The list goes on and on...
Make a list during the sea trial of everything, and I mean everything that seems not quite right. Add this list to the things discovered on survey, and seen a nicely worded letter along the lines of "we liked the boat and are still interested, but there are a number of things we need to address before moving forward." Strike from the list anything that is a diminimus cost, and see what the dealer says.
Many owners will offer up front to cover a significant percentage of the repair work, or agree to cover some things but not others.