Private repair companies have been repeatedly over-charging social housing tenants as part of a £220m contract, a whistleblower has claimed.
A former worker at the housing association which pays for the repairs of 9,000 Merton homes claimed sub-contractors working for Keepmoat Property Services were routinely over-charging for work.
Residents end up paying the bill, either through increased service charges, or indirectly through their taxes which fund the works through housing benefit.
Keepmoat said it was taking the allegations extremely seriously and has ordered an investigation into the claims.
The building company was awarded a five-year contract worth £220m in January 2013 to provide responsive repairs for more than 17,000 homes in Merton and Kent.
The whistleblower, who was a customer service advisor at Circle Housing Merton Priory (CHMP) for more than eight months, told the Wimbledon Guardian contractors regularly failed to turn up to jobs, falsely claimed they did not have enough time to complete work or turned up without the right equipment.
The former staff member provided an example of Keepmoat charging £700 for the replacement of 13 fence panels when only one damaged panel was actually replaced.
Senior managers ignored over-charging allegations when they we informed, the whistleblower claimed.
Residents have also told the Wimbledon Guardian contractors are hiking up prices:
• £30 was quoted for the replacement of a £3.20 plastic window handle by a Keepmoat sub-contractor, a Ravensbury Grove tenant claimed.
• Up to £10,000 was estimated for the erection of scaffolding to fix guttering, a High Path estate leaseholder alleged.
The whistleblower said: "The contractors put in materials orders that were excessive for the repair and I would often find out from tenants out of curiosity what work was done.
"For example an elderly lady called up to advise one fence panel had been blown down and the rest of the fence was quite new and didn’t want all the fuss.
"The contractors on this occasion put in an order for 13 panels costing over £700.
"The order was authorised and the tenant later called to advise they only repaired the single panel but the contractors claimed for and was paid for 13."
"My point is money is being wasted and the tenants are not being invested in as the website says."
A Keepmoat spokesman said: "We take allegations of this kind extremely seriously and we will look into these claims in conjunction with Circle Housing.
"However, it should be noted that formal protocols and procedures are in place which mean that all costs have to be signed off and approved by both parties before any work is carried out."
Pauline Ford, regional operations director for CHMP, said: "We are aware that there have been problems with the repairs and maintenance service and we are sorry some of our customers have not received the high quality service they should expect.
"We are working with our contractor, Keepmoat Property Services, to put this right."
The allegations come after Mitcham and Morden MP Siobhain Mcdonagh revealed in June she has received 240 complaints about repairs and maintenance from residents in the past year.
She said: "We have got to the stage where we feel like we work for Merton Priory Homes because it is just reminding them to phone people back.
"People have numerous visits from surveyors but no work gets completed. It's very very frustrating."
"I think there are lots of issues - it is the way repair requests are logged and sent to contractors and then dealt with by contractors."
CHMP said last month it had instructed Keepmoat to increase staff numbers and reduce the use of subcontractors as part of a bid to tackle the repairs backlog.
Problems with the service were put down to a combination of moving to a new supplier, changes to their service and "extreme weather" last winter.
Jana Taylor, a leaseholder on the High Path estate in south Wimbledon, said she has been battling with CHMP repairs team for the past two years to have faulty guttering repaired which is not wide enough to effectively drain heavy rainwater.
CHMP has not disputed her claim. One of their staff last week quoted her between £9,000 and £10,000 to erect scaffolding to fix the guttering at the expense of leaseholders on the estate.
Mrs Taylor said: "Either their whole systems are flawed and they are incorrectly tracking what's been done, or it's possible that Keepmoat is saying they have done work they haven't done.
"Otherwise it's just complete incompetence on behalf of CHMP."
CHMP declined to comment on Mrs Taylor's allegations.
CHMP tenant Mark Moore has worked in the building industry for more than 20 years and lived with his family in Rutter Gardens, on the Ravensbury Grove estate, for the past five years.
He said: "Keepmoat is screwing CHMP left right and centre. Over the past three years there have been so many companies who have gone bust because they couldn't cope with it and it's got to the point where CHMP doesn't care because the government funds most of it."
Mr Moore said he disputed a contractor’s claim it would cost £30 to replace a plastic window handle at his home in July 2013.
He said after getting out his laptop and finding handles online for sale at £3.20 and conceding half and hour’s labour rate is about £15 in front of a CHMP representative, the contractor allegedly backed down and the price was reduced.
CHMP declined to comment on Mr Moore's allegations.