You should consider how much cash or assets could be stolen/siphoned off in a worst-case scenario. You should also consider your business operations: how often do employees have direct access to company cash/assets? How much cash/assets do they have access to at any one time?
For SMEs turning over between $1-$3 million in annual revenue, a fidelity guarantee insurance policy with $50,000-$100,000 in coverage should be sufficient.
For SMEs with up to $5 million annual revenue, a fidelity guarantee insurance policy with $200,000 in coverage would be more appropriate.
Having a fidelity guarantee policy, together with strong accounting controls and finance oversight procedures, will dramatically reduce the risk of your business being taken advantage of (or even dealt a crippling financial blow) by dishonest employees.