Create My Business Templates!?!

I've made the bold decision to start my own small business, offering business advisory and coaching services to SME's. I've created my logo and now what id like to do is to have a suite of templates created containing my branding. I'm no Word Guru so I want something that is easy to work with... Want them to be customisable as well (eg if i want to update my contact details on the templates that you create, that its easy and doesnt result in the document turning into a mess). In your response you could suggest a series of templates that I may need, however at this stage im looking at: business proposal, report template which could be used for marketing, organisTional, stakeholder strategies etc, invoicing, purchase order, memo and presentation master slides. Attention needs to be made to text, I need aomething that conveys knowlege and strength.