Stuff happens to all of us unexpected.....I had a deal in the works a good while back and the computer got a bug, died a painful death and it resulted in a whole new system/file exchange, etc., about a 2wk mess. It underscored for me that the previously mentioned 2nd level of non-computer comm is pretty important for both parties,
Glad your situation worked out for both of you, but to answer the question posed, I guess Id go with about 2 weeks of no or bad (read: stringing you along) comm. even though I suffered through a rip-off hustler for about a month before I gave up (let GB know & dude was gone in short order too). Ya kinda know in your gut when its been long enough.......