SQL QUERY New

I have tryed to get this working for last 4 hours. Please help. The View works and when i run the query i get the count but no column name, so i use an inner query but get this error

ORA-00934: group function is not allowed here
00934. 00000 - "group function is not allowed here"
*Cause:
*Action:
Error at Line: 1,817 Column: 62

PLEASE help me.

create view Details as (select insured_item.C_model, count(policy.policy_ID) as Counter
from insured_Item, policy, insured_by, client, person
where
Insured_Item.item_ID = policy.Item_ID
and policy.policy_ID = insured_by.policy_ID
and insured_by.client_ID = client.client_ID
and client.personal_ID = person.personal_ID
and person.suburb ='Randwick'
group by C_model)

select MAX(Counter) as MaxC
from Details
where C_model = (select C_model from Details where C_model = Max(Counter) )