Hello,
You will be able to use the
CustomerSyncService to pull the changes made in the account for the past
90days. The
lastchangetimestamp will give the last changed processed for the customer. The
CampaignChangeData will return the changes made in the campaign. It is not possible to see who made the changes to the account.
You will be able to use the API reports which will return the Cost for the date range specified in the report query. The report types listed
here can be used.
Let me know if you have any questions.
Regards,
Bharani, Google Ads API Team