Excel VBA

Hi, I have a query on writing SumIf & VLookups code, where the starting point of Data is know, but number of rows could vary for e.g. Number of rows could vary between 15 and 20.

VLookups:
Is it possible to set a dynamic Table Array, where starting point is know but number of rows could vary. I tried using CurrentRegion, but got an error.

SumIfs:
If starting points of Range (with Criteria) and Sum range are known but rows could vary. Would using the code below work:

Range with Criteria:
Range("A2").Select
Range(Selection, Selection.End(xlDown)).Select

Range with Criteria:
Range("C2").Select
Range(Selection, Selection.End(xlDown)).Select

Would CurrentRegion.Rows work?

Regards,
Raman