If I can make one comment, hard won from painful experience: if there is just one of you, there are only two acceptable answers as to when you'll have something done: "It is already done." and "It is not done." Customers tolerate missing features surprisingly well, and if they don't there are more fish in the sea.
Missing promised shipping dates, on the other hand, costs you tremendously disproportionate amounts of goodwill. Making them often requires stress wildly disproportionate to the business value involved.
Example: When I started (and was stupid), if a customer asked me "Does the software do $FOO?", and $FOO was in active development, I'd say "I'm working on $FOO right now and it should be ready on $ESTIMATE." Often $ESTIMATE was about a week away. Now that I'm older and wiser, I say "$FOO is not ready but it is planned for a later version of the software. Would you like me to email you when $FOO is ready?"
This happened not two weeks ago with an enhancement to the online version of my software. It didn't support consistent columns yet (some users to call bingo games by word and column, which cuts search times for players down drastically, especially important when you're playing with older folks who don't have great eyesight). I've implemented that in Java before and thought it would take me less than one day in Ruby, and had a Saturday free. When I was young and stupid I would have said "I expect to have that done on Sunday." Good thing I didn't -- Friday I got enough overtime piled on to totally exhaust me, and I didn't get up until 3 PM on Saturday, with a planned social engagement at 6. But its all OK because my customer doesn't know any of this! It just took me until this weekend -- I sat down, banged it out, and just emailed her about it. If she buys, great, if not, none of us is worse off.
Missing promised shipping dates, on the other hand, costs you tremendously disproportionate amounts of goodwill. Making them often requires stress wildly disproportionate to the business value involved.
Example: When I started (and was stupid), if a customer asked me "Does the software do $FOO?", and $FOO was in active development, I'd say "I'm working on $FOO right now and it should be ready on $ESTIMATE." Often $ESTIMATE was about a week away. Now that I'm older and wiser, I say "$FOO is not ready but it is planned for a later version of the software. Would you like me to email you when $FOO is ready?"
This happened not two weeks ago with an enhancement to the online version of my software. It didn't support consistent columns yet (some users to call bingo games by word and column, which cuts search times for players down drastically, especially important when you're playing with older folks who don't have great eyesight). I've implemented that in Java before and thought it would take me less than one day in Ruby, and had a Saturday free. When I was young and stupid I would have said "I expect to have that done on Sunday." Good thing I didn't -- Friday I got enough overtime piled on to totally exhaust me, and I didn't get up until 3 PM on Saturday, with a planned social engagement at 6. But its all OK because my customer doesn't know any of this! It just took me until this weekend -- I sat down, banged it out, and just emailed her about it. If she buys, great, if not, none of us is worse off.