larm bells should ring if...
You are asked to disguise or conceal any payment
You are asked to use an irregular payment method
You are using an agent because they "know all the right people"
Payments seem unusually high for the goods/services being provided
Someone requests urgent payments, especially if in cash
You are asked to make a payment to "win the business" or "get the job done"
You are asked to authorise a payment but you do not know what it is for