How often to you clean vinyl and the needle?

Yes.

New or new to me used albums get cycle on the record cleaner with Last heavy duty cleaner and followed by Last Record Preservative . This typically only once.

Quick surface clean with Last General Purpose cleaner and drop the needle into a stylist cleaning gel for each play.

I clean the record before play with a carbon fiber brush, and I use a brush to clean the stylus after each play.  I use the LAST stylus cleaning fluid about once a month and the Oznow stylus cleaner about once a month, or when I think the sttylus has gotten some gunk on it.

This regimen, along with use of the LAST stylus preservative before each play, enabled my last stylus to play for over 1200 hrs. and still sound good.

Records get cleaned before first listen, even new ones. 

Needle gets ultrasonic cleaning when needed, brush it only on occasion when I see something on it. 

The less you touch the needle the less chance you have to ruin it. Have killed a needle trying to brush it. Then I got the UC cleaner, it also does a much better job. 

Those vibration based cleaners do work nicely, but they are not "ultrasonic".  The ones I know about, sold under the Audioquest brand and maybe some others, vibrate at around 500Hz.  That's why you can hear it.  I have the Audioquest version but use it rarely.