Hi,
Usually PCB manufacturers provide informations about their standard capabilities.
There is a wide range
* of application requirements
* a wide range of PCB manufacturers regarding techniques, materials, precision ...
* a wide range of cost
The close you go to the high end technology, the higher the cost, the lss manufacturers you will find, the higher error rate you may expect.
I try to go a conservative way, when possible.
And a have a couple of PCB manufacturer for:
* low / high volume,
* delivery time
* low cost / high end
Klaus