I’m doing this right now. Or I’m writing a check to a professional who will abrade the slab with a diamond grinder and apply epoxy, chips, and a clear coat. Of course your can use big box store products and get a product that looks the same until it peels next year.

I agree, DIY epoxy applications are prone to failure.

You may wish to consider vinyl floating garage floor. Mine is Race Deck. Have been pleased for several years. Available in variety of colors to create designs.

A friends floor:

Another consideration, in our last new build house my husband put down indoor/outdoor carpeting. 5 years later when we moved out, he, of course, removed the rug. The floor looked as good as it did when it was new. I'm sure there will be nay sayers, but it didn't cost $3500.00, looked good and rain water didn't puddle on the floor.

Chemically etching with muriatic acid, and all the rubber gloves, apron, and goggles, is the just about the worst part of it. Second only to 18 months later when it's peeling and you have to grind it all off. A good commercial epoxy that resists brake fluid and other garage corrosives would have material that costs more than $3500.

I was thinking of using Rustoleum Rock Solid and then instead of their top coat, using Rust-Oleum FastKote Clear UV Stable Polyurea Floor Coating on the top of it.

Do not use the Rustoleum; it does not last. We even had our garage floor professionally done with a commercial epoxy, much better! I now think the best option is a vinyl floating floor.

You need a commercial grade epoxy.

It's all about the prep work. It's important to use a concrete etching solution, as well as fix any cracks or major gashes. Also be sure to remove anything stuck on the surface of the floor.  I've used both the regular Rust-Oleum epoxy flooring and the Rustoleum professional epoxy. I would definitely go with the professional version as it is solvent based and I have had no issues with tire peeling after 10 years. You will probably need more epoxy than what they claim if you want to get a nice thick coat.  I ended up using nearly three of their two car garage kits for a three-car garage.  There are higher quality 100% solids epoxies available online, but some of them are harder to spread and will cost more. Since most of the work is in prep, you may want to consider whether it's worth upgrading to a higher quality product so that you don't have to redo it down the road.  With that being said, there is totally unprofessional has been extremely durable. My only complaint is that coolant or oil will stain the floor if it sits for a long time. However, using plenty of color chips (buy extra) will help to hide any stains.

That should say "the rustoleum professional has ben extremely durable"