Hallo!
First of all - if you are interested in payment in advance - ther will be no such a thing. 
Working with Tuelancers for a 23 projects from 3 different companies, only 7 was succesfull all other was a mess - sorry

I need Laravel devs for a longtime cooperations - but really good ones.

The project is: b2b e-commece website.
There is no defined technical specification, but there is a knowledge of what is needed an i am always online for chat and emails