How can I effectively seal my whitewashed Travertine floor on a tight budget to brighten up my kitchen?

Hey there! So, I was on a bit of a budget, but really wanted to give my kitchen a little facelift. I decided to whitewash my old Travertine floor. Now I’m wondering about the best way to seal it. I was thinking of using a water-based poly, but I’m open to any suggestions or recommendations from others who have experience with this. And by the way, here’s a sneak peek of the progress – the before and after photos (oh, and don’t worry, we’re keeping that gorgeous vintage range, just not in this space)!