Hakaoro asked them for $3000 to help with their application, $3000 to provide job offers and later asked for another $2000 to pay for his immigration adviser licence.
Less than six months later the couple was told they had to leave New Zealand as no visa applications were submitted.
In 2010, Hakaoro offered to help a woman, her mother and her husband. The three handed over $3750 and were asked for another $3000 for Hakaoro to travel to Tonga to obtain police records and check their immigration status.
When the women become unhappy with Hakaoro and her son tried to intervene, Hakaoro threatened to call Immigration NZ and dob them in for being in the country unlawfully.
Another couple was told by Hakaoro that he had worked for Immigration NZ and could get visas for them and his family.
The couple's daughter took out a loan to pay Hakaora's fees only to find no visa applications were submitted for their family.
Judge Eddie Paul told Hakaora: "Your victims were vulnerable people, anxious to secure their status in this country. One can hardly think of a more vulnerable person than one in a foreign land being offered an opportunity to remain in that foreign land when the reality was that offer was unlawful and delivered in a deceitful way."
The judge said home detention would be inappropriate.
After his release, he must repay his $5000 to his victims at $20 a week.
Registrar for immigration advisers Barry Smedts said in a statement the sentencing was a "great" result for the Pacific community and the case showed anyone on the receiving end of poor immigration advice could turn to the authority for help.
"Several people affected by this case were in New Zealand unlawfully. It's thanks to them having the courage to speak out and work with our investigators that we were able to bring this man to justice."