Cowboy builders who dupe householders with sky-high prices for work around the home could be driven out of town by a new weapon in the war against conmen.

Cowboy builders who dupe householders with sky-high prices for work around the home could be driven out of town by a new weapon in the war against conmen.

An indispensable new guide outlining how much various jobs should cost wherever you live in the country was due to be launched at the Autumn Ideal Home Show today .

The Property Makeover Price Guide, the work of the Building Cost Information Service (BCIS), is the first book of its kind for the general public and contains advice about how to budget for repairs, improvements, alterations and extension work

It covers everything from inspecting blocked drains to fixing window panes, replacing chimney pots and doing a loft conversion and gives a good idea of how much to pay in a bid to protect consumers against “too good to be true” quotes and excessive charges.

All jobs are categorised into sections for different aspects of the home and given a price average for the UK.

Homeowners in East Anglia should then multiply that figure by 1.01.

For example, the average UK price of a 3m x 3m single storey extension with one window rises from £17,000 to a realistic quote of around £17,170 in East Anglia.

BCIS spokesman Joe Martin said: “If you are seriously interested in knowing how to employ skilled labourers to undertake work on your property safely and legally for a fair price you will not be disappointed.

“Knowledge is power and we expect this guide to demystify construction and help drive the cowboy builders out of town.”

The guide is aimed at people who want to improve their own home and novice property developers, but it also could be of use to the elderly, who are often seen as a soft target for unscrupulous workers.

In March this year, conman William Gaskin, 29, was jailed for three years at Norwich Crown Court after he admitted overcharging two elderly women more than £17,000 for building work.

He had quoted a customer in Hunstanton £1200 for guttering and fascia work, but charged her £7900, and overcharged an 82-year-old in Cambridgeshire by £12,335.

The Property Makeover Price Guide is available from BCIS at £17.99 by calling 0207 695 1500.

Price guide for jobs in East Anglia

Replace gutters and downpipes (PVC, whole house) £691 for a terraced house to £2,070 for detached

Hang vinyl wallpaper (£8 per roll, 14msq) £373

Two coats of emulsion paint (14msq) £146

Replace heating system (including digital programmer) £4,262 to £6,383.