I have a 20 ton Blackhawk frame ( circa 1990 ) that is made from rolled angle / channel. The hydraulics are a Enerpack hollow cylinder and hand pump ( 15 T ? ) . It is very stiff and does not move around when loaded.

At work we have a 10 ton formed steel press with a bottle jack as power. Making setups is difficult because the press is out of square and twists when loaded. Thankfully I don't get into heavy pressing with it.

Having a press is only part of the operation, you will need various tubes , rods, old bearings, squares as tools. Also be aware that an off center press tool setup can slip and throw parts / shrapnel at great speed.