I prefer an Overhead jib or gantry crane they are very easy to make
and move.
the Machine I wish to make has only its Gantry above its working table making things easier to put on and More important Taking off without damaging using either clamps or Vacuum lift regarding heavy objects , straight onto a waiting vehicle or storage area.
I don't do granite worktops and all the gravestones I do are Hand cut and hand finished.
Raised side rails prohibit the full use of the table, as most lifting equipment needs its own space usually 100mm margin area.