Insist on receipts for any funds handed over.
Be wary of the agent or intermediary offering significantly more than the going rate for funds - study deposit interest rate tables in the newspapers to establish the going rate for deposits and shop around to establish the going returns on investment products.
Find out who are the regulators for the different intermediaries and institutions and if in doubt check with the regulator.
Check that the intermediary is authorised to take in deposits/ investments. Do not rely on the fact that the intermediary has already arranged your mortgage.
Avoid the agent or intermediary who does not display his/ her authorisation to act as an investment intermediary or appointment as a deposit taker.
Avoid the agent or intermediary who is reluctant or unwilling to discuss the commission he/ she will receive on the different investment products you are being offered.