How do I know if a supplier price is suspiciously low?

An unusually low price is a signal to look at the specification, not a reason to celebrate or to accuse anyone.

Start with the battery, because it is the single largest swing factor on an electric forklift. A quote with a smaller capacity pack, or without the charger, will look dramatically cheaper while describing a machine that cannot do the same work. Then check the mast: two stages versus three, with or without free lift, changes both capability and cost. Then attachments, tyre type and packing.

There is also a listing-level trap worth knowing. On some marketplaces, the headline price on a machine listing is a deposit or a deposit-like figure, not the machine price at all. A number that seems impossibly low is sometimes exactly that — an enquiry deposit — which is why we do not use listing prices as reference prices on this site.

The reliable method is the same one that works for comparison in general: write the specification down, require every quote against it, and treat any unstated item as not included. Then a low price either becomes explainable or it does not.