For the first requirement please refer to the Profile Option ICX: Numeric characters and make sure XDO: Numeric Characheters is pointing to this profile option.
For Comma Separator of 1000's, you may need to enable Currency:Thousands Separator to 'yes'
Bounce oc4j (iAS/Apache) and clear cache, and then retest to confirm
For the Second requirement, you will have to personalize the OA page, please refer to guidelines as per note:
How To Restrict Entry Of Decimal Value For Fields Such As Price On Purchase Order (Doc ID 1376060.1)
Similar to the personalization done in the form, get an OA developer to do it for the BWC Pages.
For first requirement , I have tested with setting the profile options ICX: Numeric Characters and also change the Number Format at User Preferences But in Buyer work Center (BWC) , Format is getting changing at Headers Values But not at Lines and Pay Items Level.
Our Requirement is to have the Number Format at Lines and Pay Items Level in BWC.
For Second Requirement, In OAF Pages , we don't have any property in Personalization of OAF Pages.Is there any other way we can have achieve the requirement.
For the first requirement I have myself tested, the decimals are updated at line level. Please see the screenshot below.
For requirement 2 - Refer to the forms personalization, similar needs to be done on OA page, its simple and an OAF technical resource is required to do this activity. You would not be able to do it from the LOV's of the available fields.
Can you please share the definition of this line type. I believe, fixed Price services should have the value basis as amount.
I do not fully agree with the way this line type is defined.