He said he was grateful to the vendors who heard about the situation they were in and wanted to help them out.
"Looking for a house is hard but not impossible," he said.
He and his partner worked really hard and most of their deposit came from their KiwiSaver accounts.
The vendors, who wanted to remain anonymous, met Mr Wilkinson and Miss Caccia-Birch at the first open home and said it "just felt right" to offer them the house first.
The couple, who have lived in Tauranga all their lives, had a similar experience when they were looking to buy their first home more than 20 years ago and they did not think twice about "paying it forward".
The vendors said they did not think about how much more money they potentially could have sold the property for at auction and were happy with the offer from Mr Wilkinson and Miss Caccia-Birch.
Simon Anderson, Eves and Bayleys Realty Group chief executive, said this was a rare occurrence but was fantastic for the young couple.
"We know there's a lot of talk in the market about the difficulties first-home buyers face, but here we have a young couple who have done their homework and it's a nice outcome."