Vehicle electrical problems?

2001 Honda Civic EX
75,000 Miles

So before I start my spiel, there are probably going to be things you'll laugh at, and some may wonder why this is even a question.
With that being said, this is an actual issue that we're facing and yes, I know the driver in question is a complete idiot.

Without further ado;

My boyfriend is not very good with cars. In fact, he goes through them like underwear. That is why I told him that his next car is going to be an old Civic or a Camry because you dang near have to try to break those.
Well, low and behold; we had flash flooding in our area for the first time in a long time.
My boyfriend was driving down a very busy road during rush hour and everyone, including him, drove through knee high water.
He was among the lucky few that actually made it out.
As expected, the car did not make it out unphased. The car has issues starting every once in a while, the radio displays an "error" message, the turn signals sometimes blink very fast, and it has random electrical cut outs while driving.
Now, when the electrical does cut out, everything comes back on within a split second.

With all of that being said, Honda believes it's because his alternator is going out, but wants $150 to test the alternator.
Now, I find it really hard to believe with all things considering, it's the damn alternator.
But I'd like a second opinion before I spend $150 just for them to tell me it isn't what they said it might be.

Sounds like it has way more problems than the alternator. Might be cheaper to get another Honda or Toyota.- and of course avoid any flooding water.

Having other problems doesn't mean that the alternator is good. Go to a parts store. They can usually test that for free.

Go to an auto parts store. They test batteries and charging systems for free!

Go to an auto parts store. They test batteries and charging systems for free!