Castledene, the inspirational lettings office in County Durham, is to more than triple in size over the next five years.

It also says that its new sales operation is proving a major success.

The firm – many of whose tenants are on benefits, and which was featured in a TV documentary – is to roll out sales across all of its branches.

Three branch openings and two acquisitions are due this year and managing director John Paul said the firm plans to open three new branches a year for the next five years.

Castledene currently has seven branches and was started by Paul on £500 in a back bedroom just seven years ago.

He added: “We went into sales last August and immediately hit the ground running, averaging over seven sales per month from a standing start.

“After three months we were ahead of our business plan for the year and started to make a profit after month four.

“We take a very proactive stance and are big on customer service, so update vendors and sellers as much as we can just to give them peace of mind that we are in control of the situation.

“We are also very realistic with our valuations and never over-value just to get stock on.

“All our staff have huge experience in the industry and we don’t mind paying more to get the best, as ultimately the customer benefits from their experience and quality.”

The company will be rebranding its Internet letting agent office in Seaham, Co Durham, as Castledene Sales and Lettings in March. Two new branch openings this spring will have the same Castledene branding when they open in Hartlepool and Consett.

The first acquisition is likely to be announced shortly by Castledene, which won last year’s Times and Sunday Times national letting agent of the year title.