You'll double your investment cost if you go with an electric. Northern and HFT both have them, $99 and $129 respectively. I'm optimistic and would trust either.
Absolutely. The cheapies come in the kits, or buy a really good one with water separator. I put a nice Racor on the diesel tow truck for an employer a couple decades ago.
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similar. They do separate the water in bad fuel, too, which you might
be receiving for that price. Be safe. Get backup bung wrenches, too.