The construction industry has a large number of self employed subcontractors covering most trades, they often work for a variety of Contractors on multiple sites, which generally means that each year they need help with their self assessment returns.
Here are some suggestions to help:
1. If you are paid net of deduction makesure you have a complete set of Payment Deduction Statements http://www.hmrc.gov.uk/forms/cis-payment-deduction-statement.pdf these statements show how much tax has been deducted and you will be able to use these statements to reclaim that tax on your self assessment return, often the CIS deductions will mean that too much tax has been paid
2. Travel – Self employed workers claim all of their travel and motoring costs and exclude a % for private use
3. Clothing & PPE – gather together all the receipts you have for specialist clothing and PPE
4. Vehicles, Tools, Plant and Equipment – these items of expenditure may be eligible for Capital Allowances and the Annual Investment Allowance (£25,000 for 2012/13) if you have any private use then this will need to be assessed and excluded
5. Other Expenses – You will need details of Insurance, Accountancy, Materials, Bank Charges, Phones, Stationery, and anything else you spent money on
It might seem boring but collecting the information noted above could save you thousands.