So, you’re worried that they are contacting you last because they consider you incompetent, but not as incompetent as anybody in their current employ? And you’re worried that how they think about you will make their money taste like ashes in their bank account? And that by taking the job they’d think less of you than if you didn’t take the job?
(I can certainly see a downside; I was doing contract work for a former employer; the hourly rate was nice, but I eventually got so frustrated with all the things that frustrated me while I worked there that I could no longer bring myself to work. A pity. I could have made a couple of extra thousand that year.)
It’s not that I think that they think I’m incompetent - isn’t it that they want me to give them info for free, info that I documented all those years ago, but now they can’t find it?
I once had a boss say “don’t say to no to them, make them say no to you” and isn’t that going to make the decision easier for you? Because while $500 per hour seems outrageous when you put a 50% deposit requirement on it, won’t they stop calling you when they know that’s going to be your response?
Didn’t I once get called about three weeks after starting a new job to ask if I’d come back at a higher wage? Didn’t I literally laugh out loud when they asked?
Have a bit of fun and see how much it is worth for them to get your knowledge? You could get say the price of nice short trip to Hawaii out of it couldn’t you?
