Ilive in the northeats, and when you park your car in the winter (which is when the garage is used) the melting snow goes onto the floor and water is "soaked" through the concrete. NOW, if putting a poxy or sealeant on it, that would prevent the water form soaking through, right? Does anyone have a painted floor who lives in a snowbelt region?

I just finished mine last week. I used interlocking tiles for the main floor, and epoxy for the upper landing area. You might want to get a few more quotes, as $5/ft for the epoxy sounds on the high side. I've seen it advertised at Home Depot for about $2.50/ft. You're correct that spills can get between the tiles. That's definitely a downside, but I view the tiles as essentially permanent. The next owner of my house can worry about it if they want to take the tiles out. You could also do a vapor barrier if you're really concerned - something simple like heavy plastic sheeting would do the trick. Here's a couple photos.

Yes, it’s a garage floor. And it has not received a single blemish, chip, stain, peel, or scratch in five years. There’s a reason as to why that is. I paid a lot of money to have an Epoxy coating on it for protection. Scratches are very, very uncommon. The guy was actually surprised that it happened at all. Obviously, not surprised enough to fix it for free - but surprised nonetheless. I consulted with a few companies and they all said the same thing. Full sand down and roll a fresh clear coat. Most people would just deal with it - but my OCD says no. The floor installers also managed to scratch two ”scratch resistant” planks of the laminate flooring they installed by also dragging equipment. But thankfully, they will replace those for free.

In my neck of the woods (expensive Canadian City on the West Coast), an epoxy job STARTS at $7 - $10/sf and moves up from there. Garage floors are tricky because the slab does NOT have a vapour barrier underneath. It is an added expense to the builder for an uninhabitable space. That means the slab is sitting over DAMP earth...all the time. Where does that dampness go? Into the garage. What happens if you coat the garage slab with a 'slap down' coat of DIY epoxy? The moisture builds up in the concrete and EVENTUALLY bursts through. That moisture, sitting on top of concrete but UNDERNEATH the epoxy = peeling. So a proper epoxy job should include scarification (grinding or shot blasting), Sealant (moisture mitigation) and then the coat (or 2) of epoxy. If you are in a rainy or snowy area of the world, you will need to add some grit to the surface. No problem...but it is an 'up-charge'. Just be aware of what a GOOD epoxy application LOOKS like. And then compare that to the quotes you are getting.