Would You Grant Service Access for Automated Invoice Collection?

I'm working on an invoice management project where users currently have to manually upload invoices from their various services. I’ve been exploring ways to automate this process by having users invite me (or the system) to their services. This would allow the project to retrieve invoices directly and upload them automatically. However, my main concern is how users might perceive the security aspect. Asking them to connect a 3rd-party service could raise red flags, especially since not all platforms provide granular roles to limit access to just billing details. Would this approach scare potential users off? How do you think I can address these security concerns effectively? Or am I overthinking this? Would love to hear your thoughts or experiences with similar challenges!