You have the problem of an Oral discussion vs Oral contract vs a written contract.This is a sad case as both of you made mistakes; you orally made a suggestive remark which he took as a promise.IMO, you ought to pay him for his time+effort and refuse the rent change.You better start documenting who said/did what when, make the good will gesture, and try to stay out of Small Claims.

I thought my nice gesture would pay off, but I'm starting to doubt it. 

It's up to you if you want to be more generous than that.It's also 60 days notice to raise the rent, when it's over 10% of the rent.In case you don't have it, I highly recommend this book:http://www.nolo.com/products/the-california-landlo...Congrats on your inheritance!

I can't believe you'd be so generous!"  

Your tenant is being generous offering the 3 month pay out. 

If they persist on wanting more money, tell them that your understanding is that what you've offered them is actually generous, but if they want a judge to decide that's up to them, and you'll be happy to abide by whatever a judge decides.  

If he can meet the rent requirements on his own (and 14 days to pay is pretty generous) then he gets to stay.Don't be surprised if he contacts you asking if his new bedmate can be added to the lease now that the wife is gone. 

My experience was that the HR Dept would be very helpful and generous with information regarding their employees who were relocating from other countries.  

The 50% sounds generous and I would recommend you take advantage of his / her poor business decision making for as long as possible.

One apartment had everything needed, was unusually well maintained, a great location, very generous square footage, nice bathrooms, and plenty of natural light.