I’m still waiting for mine to be shipped. But making the table now. I’m doing mine at 62"X62". I’ll build another table that will sit next to it that will have the computer and storage for endmills and stuff.
48" high seems pretty tall to me. I want the work surface to be about 36". That will match the rest of my work benches and tables in my shop.
Quite a few people have ordered the Kreg 64" X 64" metal table and used their own material for the top and/or shelf. Just reinforce the top so the heavy machine does not sag over time. You can certainly make your own using 4x4 and 2x4s but the cost is relatively the same getting the Kreg but you can calculate that price. I would definitely put wheels on it. Everything in my shop is on wheels and it makes it much easier to do maintenance and cleaning and if you decide to reorganize it is easy to rearrange things.
On the kreg.com site the 64" x 64" table is $369.00 but I think you could shop around and do better.
If you do get wheels get ones that lock in both directions. There is a lot of momentum on the table with the heavy machine and rapid movements.
It allows you to use the wheels when you need and “retract” when you don’t. You can also get plates for these that allow you to remove the wheels when retracted and use them on any other tool that has a set of the plates.
I have these on my CNC and Router table. I will say that when you lift the lever to disengage the the wheels it can be a little abrupt so you need to have a good hold on the table to ease it down.
Someone posted a picture last week of a table that had trailer jacks on it. That seems like a great idea if you can afford the space. It would be more gentle.
I have a differtkind of retractable wheel on my lathe, but that one requires crawling on the floor to engage/disengage and it adds height to the large which is not ideal for my vertically challenged frame.