An armed robber, who was involved in a ruse to trick a 14-year-old, forced his way into the boy's home and broke his dad's neck while demanding cash mistakenly believed to be inside.
A week later, the man burgled another home while armed with a knife and a crowbar.
Troy William Graham, 26, committed the violent crimes to fund his "ongoing and persistent problems with drugs", the ACT Supreme Court found on Tuesday.
Graham previously pleaded guilty to joint commission aggravated robbery, unauthorised possession or use of a prohibited firearm, unauthorised possession or use of firearms, and aggravated burglary.
On Tuesday, Acting Justice Peter Berman sentenced Graham to eight years behind bars with a five-year non-parole period.
Agreed facts state the day before the robbery a co-offender contacted the 14-year-old boy arranging to buy a vape.
A video showing $3500 in cash had been posted on the boy's social media accounts. However, this video was not created by the boy who never had the money.
On July 11, about 1.30am to 2am, the child opened the front door of his home to find Graham and another man standing outside.
The men "overpowered" the boy and entered the home. When Graham pointed a sawn-off shotgun at the boy, he ran.
The boy's father, who was woken up by the commotion, told the robbers to "just take whatever you want and leave".
One of the robbers responded: "We want the money. Where's the money? Give us the money now or I'll kill youse [sic] all."
The men then started punching and kicking the father before Graham struck the victim with the butt of his firearm.
The man's wife tried to intervene saying "you touch my husband again, I'll kill you".
In response one of the robbers said: "Shut your mouth c---, or I'll punch your teeth in".
The woman tried to go to her husband's aid and pushed Graham in the chest, before one of the robbers struck her forehead, knocking her to the floor.
One of the attackers then dragged the 14-year-old by the hair to his bedroom, where the boy gave the robber vapes, an iPad and a green bag containing confectionary, baby photos and dog photos.
When the child offered to give the man more of his property, the robber said: "No, I want the money".
At one point during the attack, one of the men told the boy to get on his knees. The child felt something cold on the back of his head and heard the robber ask "where's the money?"
A third robber, described as "stoned" and armed with a black handgun, prevented the boy from running out the back door.
Eventually the robbers stole six firearms and ammunition after forcing the father to unlock a safe.
A week later, Graham, armed with a knife and a crowbar, broke into another home with a woman who had a baseball bat.
At one stage, two residents appeared and there was a struggle. The female burglar threw a pot plant before fleeing with Graham.
On Tuesday, Acting Justice Berman said after the attack the father was required to wear a brace for six weeks after fracturing a vertebrae in his neck.
As a result the dad is still unable to preform his full work duties, and stand or drive for long periods of time.
The judge said victim impact statements revealed the "unsurprising devastation" the family suffered after the robbery.
He stated the boy had attempted suicide and now "had no contact with the real world outside of his house".
Graham will be eligible for release in July 2027.
