The single most expensive mistake in crane buying is specifying by headline tonnage. A "40 tonne" crane does not lift 40 tonnes at the radius you actually need — it lifts 40 tonnes at its minimum radius, on full outriggers, with the boom retracted.
Start with three numbers
Before you look at a single machine, write down the heaviest thing you will lift, the furthest horizontal distance from the crane centre to that load, and the height it has to clear. Those three numbers pick the crane. Everything else is commentary.
Then check the ground
Outrigger loads concentrate the whole machine plus load into four pads. On soft ground or over a basement slab, ground bearing pressure decides whether the crane can set up at all — and it is the check most often skipped until the day of the lift.
Then check access
A rough terrain crane that cannot get through your site gate is worth nothing. Measure the gate, the turning circle and any overhead obstruction before you sign.
