I have perlitie I could mix with Happy frog growing medium, if I feel the plant needs repotting, a 4.5 inch pot sounds kinda small to me. I'll check the drainage holes and see if the lily is in active growth when I get it.
It still awhile before the sale, May 8th, I'll maybe make a video of it when I get it and post it on here. I'll have one of my staff help me with getting it online. Do you think it'll be safe to have it outside that soon ( the 8th of may) or should it be indoors until mammoral day.