Marc Jones forced his 74-year-old victim into releasing equity on his property and taking out loans to pay for the work which has left him in serious financial trouble.
Jones, who traded under the company name of Home Improvement Centre, would drive the victim to the bank and then take thousands of pounds at a time from him.
Leeds Crown Court heard Jones “wore down” the victim by constantly contacting at his home in Huddersfield and convincing him he needed building work doing.
The pensioner now owes £47,000 and suffers sleepless nights worrying about what he did and how his debt is escalating annually.
The surveyor who examined the work deemed it to be not fit for purpose and overcharged by £16,000.
A judge who sentenced Jones described the offences against the elderly man as “insidious and wicked.”
In another offence, Jones targeted an 81-year-old Alzheimer’s sufferer in Morley, Leeds, and persuaded her to have work done for £1,500 that was only worth £400.
Jones and his son Nathan also operated a company called Adjust 4 Life.
Pensioners were sold mobility aids, chairs and beds on finance at extortionate rates of interest despite the two men not having not a consumer credit licence.
Jones, of Goosehill Lane, Normanton, also charged 31 people VAT for building work despite not being registered and fraudulently obtained £30,500.
He pleaded guilty to two offences of contravention of a directors disqualification order, two of operating without a consumer credit licence, engaging in an aggressive commercial practice, engaging in a commercial practice which contravenes the requirements of professional diligence and fraud.
Jones was also ordered to pay £10,000 compensation and was banned from being a company director for 12 years.
Nathan Jones, of Bridgegate Farm, Walton, pleaded guilty to operating without a consumer credit licence.
He was ordered to do 80 hours unpaid work and pay £500 costs.