Hi Claire,
There is no set rate you can claim for specific payments of this nature. The simple rule is; if you have a receipt, and it is wholly and exclusively for the purposes of the business (or, at least, the claimed element is) then you can claim it.
If you don't keep your receipts, then your options are limited, Far better to keep all receipts, and try to come up with a reasonable estimate of what the business / personal split is for your tax return,
You can claim a 'round sum' allowance for working from home, which is designed to cover all busines expenditure, but, without receipts, this is restricted to £2 per week, or £104 per year.
Hope that helps.
Alan
