I've done a fair amount of that - some mistakes I've made -
1. Not getting money up front
2. Extending credit
3. Open ended meetings
4. Being insufficiently explicit about what is being delivered
5. Working on a handshake (seldom a problem with big clients actually) - get them to sign something
6. Not actually meeting in person at least once
7. Not being clear on who owns the code/technology (if you're going to do more or less the same thing for the person across the street then make sure to let the client know that they are getting a license (or something similar))
8. Scheduling meetings in their downtime, but your worktime
9. Not having a template, or even an idea of what a good referral would look like
10. Having a specified finish line - much more important for the smaller client than the larger ones IME
1. Not getting money up front
2. Extending credit
3. Open ended meetings
4. Being insufficiently explicit about what is being delivered
5. Working on a handshake (seldom a problem with big clients actually) - get them to sign something
6. Not actually meeting in person at least once
7. Not being clear on who owns the code/technology (if you're going to do more or less the same thing for the person across the street then make sure to let the client know that they are getting a license (or something similar))
8. Scheduling meetings in their downtime, but your worktime
9. Not having a template, or even an idea of what a good referral would look like
10. Having a specified finish line - much more important for the smaller client than the larger ones IME