You don't need NDAs for all.
But the vendor might be sharing information with you that they feel needs protection; IP, trade secrets, SOC report etc.
Keep in mind you can only get a SSAE18 SOC 1 or 2 report if there's a contract; so an NDA is advisable as a means to cover that requirement.
A SOC 3 report can be shared publicly, but it's useless for Due Diligence. :-)
Also, a good practice is to expressly state the reason for the information sharing, so it's clear what's being protected.
Helps with enforceability should you need it...
That said, your master agreement is likely going to cover confidentiality; so if there's nothing sensitive being shared during the sales process; I'd rather just work on the master terms.
Good Luck!
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Bradley Martin
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