The buy down would put me at $550k remaining on the note; leaving a delta of about 150K year 5.

If you aren't trying to do the same thing as me at the same speed as me with the same risk as me, what I would do in your position quickly becomes irrelevant.

There was a lot of meat on the deal, so the bank was very willing to make it work!

It is amazing when you prepare prepare prepare and, when you FINALLY take action (took me at least 4 years to get started), what opportunities present themselves. 

I also received a suspicious email in BP proposing that they could lend me at 4%.

We finally get a handwritten PDF today with rates and terms and she's got me at 4.875 and $6900 in fees on a $140k loan.

Sorry, didn't meat to sound rude - your post wasn't showing up (only the title was) for a few minutes. 

An investor will need a lot of "meat on the bone", especially in this environment and depending on your market.  

The little regional banks and credit unions will always lag a bit -- it would not surprise me at all if that 95% c/o product went away 2-3 weeks ago, but the "non-essential" website update people have not updated it yet. 

Less meat on the bones.