A proposal really is a good idea, even with the really small stuff. Especially with people who are the least web-savvy, it can take loads of time with emails back and forth explaining every detail of what'll be provided and what won't.
Questions like what hosting is available and how much it will cost, what would be a good domain name, what keywords would be good - the list goes on, and those are actually part of the consulting phase of doing a site. Some people, however, want to know these things in advance. And chances are they won't want to do it, or it may be someone we'd rather not do business with which is very possible in some cases.
I just had a lady doing that - after several long emails over a period of a week she actually sent a detailed list of what she expected - nothing like what she'd been told. I finally put a demonstration contract up and she got scared at the though of making a commitment, even though not even asked to. She responded with saying she'd like to change a few of the points.
This had a lot of value to me. Although it's very seldom that this happens, every single point that was brought up wth this is something that should be spelled out in a proposal, which would be different for a small one-keyword site like this would be than for larger more complicated ones.
There could possibly be more than one proposal made up, geared to different types of businesses that might inquire and for different levels of service.
Someone once mentioned that they tack a 50% PITA fee on top of their regular fees for some clients, and after an email or two it's evident who they are. It's something definitely worth finding out right away, so as much provision can be made in advance. It's amazing how much some people can come up with.
With a proposal (or contract) for straight web design each step is easy to spell out - including having a set number of hours of consulting time, like 2. The potential for email is tremendous - the all time high was 93 and recently the runner-up was 66 in a month - now a former client of course, because I asked her to collect all the emails she'd sent (after explaining how to send update information about three times in detail beforehand) and condense them or I'd have to charge her by the hour for sorting through.
It should all be spelled out in detail so there's no mistaking it. So many graphics, so many pages, so many products, what the consulting will include, so
they know it's AFTER they pay the deposit that questions start and what they'll cover.
With SEO it's a different story. Sometimes they want detailed information so they can go ahead and learn and do it themselves. Other times it's a legitimate concern. There again, it's a matter of spelling out in generalities without giving specifics for a particular site. That can take some practice in doing. Sometimes I'll send people to a particular board thread. I consider people posting at a message board a different thing from giving a one-on-one personalized free correspondence course to a "potential client", which it can turn into if you let it.
It's understandable that people who don't know are wary, but spelling everything out without giving specifics should serve to make them comfortable. Saying you'll do 5 keywords is not the same as telling them which ones, where they go how to link them, how to get links, etc., after which they'll want to know why you're choosing them and why everything else is being done. That's the difference.
Spell it all out as much as you can based on your experence and what you can find, and add to it as you go along. The lady last week gave a pretty thorough updated picture of what needs to be made up - and she won't write it telling me what she'll get. I'll write it telling her what I'll give for so much, and that will be it. These occasions are not frequent, but they're very educational in re-thinking terms and conditions.
This will not go on a site, it will be an email template or a password protected page.