Electronic data will be exchanged preferrably via my OneDrive account. This is more secure than the exchange via e-mail and the amount of data is not restricted compared to some e-mail providers.
Especially in specific projects or whenever documents/data have to be handled by more people, Trello and Microsoft Teams are excellent tools for such collaborations as well as for exchanging files.
All data will be handled strictly confidential and I guarantee highest discretion. If necessary due to a high workload I will hire a subcontractor, who will underlie exactly the same conditions via a contract as I do.