Self employed IT contractor

Hi
I'm hoping someone could give me a little advice. My husband started doing IT contract work approximately 1year ago. He has registered for VAT, invoices the company monthly and makes his VAT returns. No probs there.
He is not trading as a ltd company.
My question concerns his tax payments due for Oct this year and the expenses he can offset against his income.
Can he offset some charges for ESB,phone, internet etc for room used as office in our home?
Car? - can he offset service charges, insurance, tax, petrol expenses etc?
In a nutshell, any help with what should be considered would be appreciated.
Thanks in anticipation.....

Afaik if he uses his home as an office he can claim a certain percentage Say 1/6 of light and heat and for mortgage/rent also can claim any repairs or maitainence of his office( Insurance and cleaning of office). altho he may have to inform insurance company that he is using the home as annoffice same applies to the car use.

Home phone he can claim approx. 50% of his bill for business calls with mobile i think he can claim all of this bill and i think 100% for use of the internet. He can claim either petrol or for civil service mileage rates. i use the latter as its easier than keeping all the receipts but he must keep a record of business trips he did and the purpose Revenue has a list of the civil service mileage allownaces.
I doubt if he can claim for car insurance. But he can probably claim back Vat on the services if he gets a vat invoice from garage.
he can also claim for meals out that were used for business puposes
obviously all receipts must be kept.

If he bought any equipment for work or courses these can also be claimed, also stationery and postage, costs of travelling to work(Petrol Or public transport). technical books, subs and courses can all be claimed for.

Thanks for that,
Regarding the car however, he doesn't do business trips as such, tends to be more 6mths with a company, 6 mths with another etc that kind of arrangement. If he uses the car to get to these positions, do the mileage rates apply? Haven't kept any petrol receipts so far, so bit of a problem there. Argument that wouldn't necessarily need the car except for the theoretically the transient nature of work (Who knows where the next contract may be?)
Is there an issue on claiming part of mortgage as offset expense and you then sell your PPR, is there a portion liable to CGT because of using part of it as an office?

Can't claim mileage if your going to your usual place of work but can claim for other locations, eg. an off-site meeting,travelling to a different site or even going for the interview