Sites go out of date. You need to plan for occasional updating.
To lessen the maintainance load, avoid anything that goes out of date quickly, like a list of next month's events or a catalogue of stock, unless you're prepared to keep it up to date.
Even so, in a year or two you will probably want to change a few details, like your mobile number or whatnot. When your site is finished I will give you a CDrom containing all the code and the admin details that you need, plus a brief explanation of how to make simple changes for yourself.