+1 on a GPS unit, either as part of the fish-finder/chartplotter or hand-held.

The Standard Horizon HX300 is a solid and popular VHF radio.  Its price on Amazon has been bouncing around from $99 to the current $109 for weeks.  Keep an eye on it:  https://www.amazon.com/dp/B00AJVXA5W/_encoding=UTF8?coliid=I111490JY1WLNU&colid=2T7U2CG566Y3J&psc=1

I've been thinking of getting a VHF radio for when I go into the salt far enough to be out of sight of my car (which I haven't done yet). What should I look for in a radio? I looked at the one linked above and noticed features like rechargeable battery, floating, submersible, etc. I also saw this one that seems to have similar features at a lower price, but I'm fairly sure that I'm missing something in comparing the two.

Uniden MHS75 Handheld Submersible 2-Way 5W VHF Marine Radio - Black, $79.56

What other models should I be looking at?

Thegpsstore.com has the Standard Horizon HX300 on sale for $94 and free shipping. I bought one two weeks ago--it floats, has a light and seems like a decent radio for the money....

I've had a few standard horizon units crap out on me (2 of them) but my ICOM has been completely problem free.

Sent from my VS987 using Tapatalk

I went with the Standard Horizon HX870.  Standard Horizon have a $40 mail in rebate until July 2018 (the rebate is also good in Canada and is payable in US funds! my rebate finally arrived in early December).

There's a few features that I feel are "MUST HAVE" items with any handheld VHF marine radio:

1: Make sure you can replace the battery in the unit when out on the water.  Many have the ability to use a couple AAA's or AA's (pack a few spares with you).  Pay attention, HX870 comes with the back up battery tray, the HX300 does NOT come with the battery tray it is purchased separately...

2: DSC calling is a really good thing to have.  I not sure why anybody would buy a radio without this feature.

3: Handheld VHF marine radios are all waterproof but not all of them "FLOAT!"  They're rather useless if they are sitting at the bottom of the ocean!

Note: 6 Watts is the maximum allowed for a handheld.

I'm not sure about the USA but in Canada you must have a license to operate a VFH marine radio.