Vinyl can be plenty strong as long as you're not moving forklifts over it all day. Quartz is a great option nevertheless. How much per sq are you paying for the quartz install if you don't mind me asking?
Do you need to remove a coating from your floor or just shave off a little to get down to unadulterated concrete? Do you need to remove height or is your slab relatively flat? Check the specs for the coating you're applying. Do you need a CSP of 2-3 or greater? All those factors will affect your...
Quartz is superior to vinyl in terms of durability and when you add in a quartz cove base like joey posted its really unbeatable. Vinyl flake cove base is also doable but I don't like to do them unless an existing cove is already installed like an epoxy mortar based cove... and that adds another...
Any epoxy system should work well for you needs but if you're paying a contractor upwards of $4/sq just make sure they have a solid portfolio. Prep is 90% of the game. You can buy the best materials on the market but if the surface isn't properly prepared and the product isn't applied well then...
Timing is everything with SLC. I'd try and get some extra help if you can. Mix 10-15 gallons at a time and keep them coming. What product are you using? I like mapei and sika. Don't forget prep is everything.
Applying urethane topcoats can be very tricky. What I usually do for small jobs is have one person roll the product out with a 9" blocking out the floor left to right and then I have another back roll with an 18" then I can stand back shooting a light across the floor and look for rope lines...
What's your budget and how much are the products you're looking to buy? From my experience most industrial epoxies sell for $50/gallon but its not uncommon to see them changing hands for as low as $25/gallon.
I would do a moisture barrier/densifier like DryCrete followed by a low solids epoxy primer then a 100% solids epoxy with a poly top coat loaded with aluminium oxide. Do these jobs fairly often and they come out nice.