Please see pictures below. 400 sqf garage, with 150 sqf laundry room. Both on concrete, separated by 2 steps. 1 garage pic is from 2 days ago, the others from today (we are currently painting walls with Benjamin Moor Chantilly lace). We will make it a sort of game room (ping pong, foosball) and that is where our 2 cats will shelter. Installing 14000 BTU AC unit on laundry window. We went to Benjamin Moore store and he suggested his Gennex Waterborne Floor and Patio line since no plans to park a car (for now, but could buy new one and put it there in the future). They suggested their paint over their solvent based or epoxy. Now we are torn. I think I am ruling out epoxy and choosing between paint or porcelain tiles (veering toward the latter). Best quote for installing tiles is at $3.5 per sqf. The cheapest decent looking porcelain (not ceramic) tile with PEI 4 or 5 (would be good for future car) at Floor and Decor is $1.5 per sqf. So that would run about $3300 for the entire area. Of course I can get away with 2-3 gallons of water based or solvent based paint (~$200). But I need to degrease the floor if I wanna paint (Benjamin Moore guy said no need to prime with Gennex product). Questions are:

1) If I paint and I do not like it or it wears off quick, will I need grinding to install tiles?

2) If I go for tiles, based on the picture (garage seems unpainted), do you think installer can just put thinset on top on concrete and then tiles, no degreasing/grinding needed?

3) Do I need Ditra or some other underlayment under tiles? Ditra is so expensive, any membrane that is good enough to decouple in case concrete moves? Or any good thinset with small flexibility?

4) As for tile selection, in PEI 4 or above enough in choosing a tile that will last decades?