>Yes, i lost a client 3 times , and i get fired some time ago 2 times, that is why i am asking, it made me more insecure.

Hi,

My only comment would be - when you quote on a job:

a) are you being specific enough in your contract; in this case, does your estimate state that SQL server needs to be running and at a certain version for it to work (I cannot remember what you said you had to install)

b) are you allowing extra time for all the things that can go wrong - for most jobs, if there are some "unknowns", are you allowing perhaps 25% extra time for those things? In my experience, a customer likes it better if you come in "on budget" or "below budget" - and the only way to accomplish that is to allow for some extra "unknown" time in your quote - because there is always just about something that causes a problem.

c) are you even providing a written estimate?

Just my thoughts.
Albert