Capital One 360 Checking $50 Bonus
 

Get started and earn a $50 bonus.

Click on 'Apply Now'. (Link Below)
Open 360 Checking and make a total of
3 Card purchases or Person2Person Payments (or any combo of the two) within 45 days of account opening.
Your $50 bonus will automatically be deposited into your account on day 50.

https://home.capitalone360.com/lp-nofees

When you sign up with Captial one 360 checking account, does that mean that bank transfers from captional one 360 checking to another bank will count as ING ach push?

Don't think so sorry. Person to person payment is the easiest way to hit the minimum though.

No minimum on the purchases, right? So I could put $50 in, use it to pay bills in 3 transactions, then get my $50 and close the account on day 51?

I would clear the account and leave it open a bit longer. I don't see any disclaimer however the account has $0 minimum so can't hurt to leave it open for a few months.