What we should know before a barrel and a screw quote?

Before a barrel and screw quoting, we have to learn as below:

A. For a barrel:

1. Most important: Not only the Internal Diameter, but also the Length, and most important is the Outer

Diameter, because the cost is based on this OD;

2. Is there any barrel venting hole on the barrel? Other word is Exhaust hole?
3. Is there any feeding hole on the barrel?
4. Is there any cooling jacket beside the feeding hole on the barrel?
5. Is there any grooves inside the feeding section of the barrel?
6. Is there any other special structure on this barrel?
7. We have to learn the barrel joint size, which connects to a Gearbox, maybe there is a flange...

8. Any other requirement from a customer, such as barrel material...

B. For a screw:
1.Most important: Not only the Outer Diameter, but also the Length, and more is what about the L/D;

2.What about the screw structure, with a BM section? A Barrier section? A Mixing section? Or only a 

normal transfer from over to over? Or structures above together.  

3.If a customer really do not learn which one of a screw structure like mentioned above, the screw has to 

be redesigned by us, we have to learn more, such as the plastic material, motor, screw speed, output

demand..., the more, the better. And an additional design fee the customer has to pay;

4.The same is the screw joint sizes we need, which connects to a Gearbox;
5.Any other requirement from a customer, such as screw material...