Another option might be foldable tables, like https://www.amazon.com/Gocamptoo-Folding-Outdoor-Portable-Plastic/dp/B09BVMBCNG/ref=sr_1_3_sspa

They can be packed away easily and you can put multiple units together to create a larger build space, and without worrying the lips (higher edges) that are on the edge of proper play tables. If you wish, you could also add some coloured covers like https://www.amazon.com/Eurmax-Spandex-Polyester-Tablecloth-Cover-Table/dp/B0855CZ2RD/ref=sr_1_9 to give a similar surface colour to the typical play table.

The only major downside is likely to be that the lack of lips/edges could make it easier to roll trains and vehicles off onto the floor accidentally.