Symmetric lifts have columns directly opposite with equal arms; asymmetric lifts rotate the columns and use shorter front arms so the doors clear.

A symmetric lift positions the vehicle centrally between the columns, which suits loads with a central centre of gravity and gives good stability.

Its drawback is that the doors open against the columns, which is a constant nuisance for interior and electrical work.

An asymmetric lift rotates the columns and uses shorter front arms and longer rear ones, sitting the vehicle further back.

The driver's door then clears the column, which is why asymmetric dominates general repair work.

Some lifts are versymmetric, offering both arm configurations, which suits a workshop handling a genuinely mixed fleet.

From the vehicle manufacturer's designated points - never from what looks solid, and with particular care on electric vehicles.

Manufacturers designate points engineered to take the vehicle's weight, usually marked on the sill or in the handbook.

Lifting elsewhere damages sills, floorpans and underbody components, and can let the vehicle slip.

Electric vehicles have restricted points because of the battery pack, and contacting the pack is both dangerous and extremely expensive.

Adapters, extenders and pads are supplied for vehicles whose points are recessed or unusually shaped, and they should be used rather than improvised.

Keep a lifting point reference for the fleet's vehicles at the bay - it is quicker than looking it up and it prevents guesswork.

They stop the arms swinging out from under the vehicle as it is raised - and a restraint that does not engage is a serious defect.

The arms swing freely to be positioned, and must then be locked in place before lifting.

Most designs engage automatically as the lift rises off the ground, using a toothed gear at the arm pivot.

If a restraint does not engage, an arm can swing under load and drop that corner of the vehicle.

Check engagement as part of the daily check and again with each vehicle once the pads just contact.

Worn restraint teeth are a common finding on older lifts and are a reason to take the lift out of service, not a maintenance item to defer.

Clear-floor carries the equalising mechanism overhead, leaving the floor unobstructed; floorplate runs it across the floor and suits low ceilings.

A clear-floor lift has an overhead beam connecting the columns, so nothing crosses the bay at floor level.

That makes it easy to sweep, drive over and work around, at the cost of a height limit set by the beam.

Tall vans and commercial vehicles can foul the overhead beam, which is a real constraint on the vehicles a bay can take.

A floorplate design runs the mechanism in a low cover across the floor, so there is no height limit above.

The cover is a trip and trolley hazard and collects dirt, which is the trade for unlimited headroom.

Correct lifting points, balanced positioning, arm restraints engaged, and always lowering onto the mechanical locks before going underneath.

Position the vehicle so its centre of gravity is between the columns, accounting for any heavy load or body.

Raise until the pads just contact, then stop and check all four pads are correctly seated and the vehicle is stable before lifting fully.

Raise past the working height and lower onto the locks so the load rests on steel rather than hydraulics.

Never remove heavy components - an engine, a gearbox, a rear axle - without considering how the centre of gravity shifts as they come out.

Keep the area around the columns clear, and never leave a raised vehicle unattended with the bay accessible to others.