Recommendation to download attachment fields from CPQ transactions.

Summary:

We are creating a repository outside of CPQ and we need to export several attachments fields for almost all existing transactions, just wanted to check if there is any recommendation about using Rest APIS, or what other options we have. If there is any limitation about number of rests Api calls allowed, or any recommendation to prevent performance issues. I'm testing Rest API to get the transaction XML and then filter out filelocation value for each field that we need, however that will require one additional call to get each attachment attribute.

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