Churchcare is an excellent national CofE website for everything to do with looking after church buildings etc.
Try using Parishbuying.org for any utility or other purchases. Whether or not you take advantage of any of the deals offered, they say they can “save you time and money. Any Parish Buying supplier has undergone a rigorous selection process to ensure they can meet the specific needs of the Church of England.” Not only that but anyone that works on behalf of the church is entitled to register and has access to some of the deals on offer.
Before organising any repairs or alterations to your church, it is worth considering whether you need a faculty from the Diocese of Oxford.The Diocesan Advisory Committee operates to a certain extent in the place of the civic planning authorities, and essentially:
“Some routine maintenance work can be undertaken without any permission (work in the so-called de minimis category);
Some temporary rearrangements, for up to 15 months, may be undertaken by permission of the Archdeacon;
Most work (including quinquennial repair work) needs formal authorisation by faculty of the Archdeacon or Chancellor;
Work which affects the external appearance of a church or churchyard is likely also to need planning permission, from the local planning authority”
This is the link to the forms you will need if applying for a faculty.
Diocesan page regarding maintenance and management of parsonages/vicarages etc,