I believe at the end of the day that the costumer is the Boss, so I promote what I can do for the costumer (A happy costumer pays a fair rate for a good job), manner, knowledge and commitment, I then ask what the company can do to ensure that I am able to keep the costumer happy.
Does the company pay a fair rate.
Does a company train
Does the company have tech backup, when i am over my head.
Is the company ethical, where is only does what is required so the costumer gets good value for money.
If yes then, I am able to promote the company to the costumers with true conviction.
At the end of the day, those who are at the coal face, are the companies best sales team! (without even knowing it)