Mr Richard Tan, 50, was preparing to go to bed when he smelt something burning.
The property agent initially thought someone had left something on the stove.
It was the cries of alarmed neighbours that alerted him to the fire blazing outside his main door which reeked of paint thinner, he said.
Mr Tan swung into action. He grabbed a pot of water to put out the flames.
By then, the fire had damaged his front door and the metal gate.
It also destroyed two pairs of slippers and a pair of leather shoes left outside the two-room rental flat at Block 59, Lengkok Bahru.
His 27-year-old wife was unhurt in the 2am incident on Sunday.
But their 14-month-old son was taken to hospital for smoke inhalation.
He has since recovered and returned home.
Mr Tan told Chinese daily Lianhe Wanbao: "Luckily my neighbours helped to put out the fire. Though our main door was burnt, the fire had become much smaller when I discovered it."
Shin Min Daily News reported that Mr Tan went to sleep at around 1am, but woke up 45 minutes later to find his main door on fire.
He said his family had moved into the rental flat just two weeks ago.
He suspects loan sharks were behind the fire because he found the name "Andy" scrawled four times outside his door.
He believes this could be the name of the previous occupant, who had left behind unpaid traffic fines and over $200 in unpaid utility bills.
Mr Tan said a stranger had knocked on his door recently and asked if he had just moved in.
The stranger identified himself as a licensed moneylender, reported Shin Min.
"You see this stuff on television and the movies, but you never think it could happen in real life.
"But here it is, happening to me," said Mr Tan.
He is now worried about the safety of his stay-at-home wife and their child.
Mr Tan told Shin Min: "My wife is a housewife and my son is still young so they're often at home. I'm worried for them and can't concentrate while I'm at work in the day."
A neighbour known only as Mr Guo, 82, said residents in the block received a threatening letter from Malaysia in their mailboxes three months ago. It identified Mr Tan's unit.
The letter, which he has thrown away, demanded the repayment of money, otherwise the unit would be set on fire.
"I didn't bother about it after the previous tenant moved out," the retiree told Wanbao.
Mr Tan told Shin Min: "Before moving in, I checked out the surroundings and was very happy with it, and the neighbours were nice.
"I didn't expect to suffer because of the previous tenant's debts."
Mr Tan said he hopes to apply for another rental flat for his family's safety.
This article was first published on May 3, 2016.
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