Do you clean your records before play, after play, or once (and then never again)?

I clean records once on a good record cleaner:  I own a VPI 16.5 but have used an Audiodeske at work (at an audio/video specialist).  New as well as used ones should be cleaned in my opinion as there are lubricants used in the record manufacturing process that need to be removed.  Usually I only clean them again if accidently fingerprinted, or if listening reveals something noticable has "landed" on the record and an annoying pop or click has suddenly appeared that wasn't there before.  Only use an Onzow stylus cleaner.  Our stylus microscope reveals it's very effective at removing  grunge from the stylus--better than most brushes and fluids!  PLEASE, please don't use a Magic Eraser as some suggest!!  I had one customer come in with a hopelessly clogged up stylus that took me many minutes to clean and guess what he was using?  Yes the Magic Eraser!  Folks, M. E. is NOT a good stylus cleaner!  It can leave a lot of stuff behind on the diamond that can clog up your stylus so badly it prevents proper playback!  Use an Onzow and be assured it will be clean.  I use one most every record just to be sure I'm not transferring dirt and debris from one record to another. My records sound clean and there's some I've owned and played quite often for over 40 years!  Trust me!  

For record cleaning, I have two vacuum units- a KAB EV-1 that uses our home vacuum for suction ($169) and a VPI 16.5 ($700 but I know a dealer that discounts them.)

All records get a deep clean using the KAB. The VPI is used as a maintenance/before play vacuum.

Deep Clean:

MoFi Pure Enzyme: 5 minute soak per side
Vacuum with KAB after each side
Spin Clean with fluid at 2x recommended strength using Aquafina water
Vacuum
Fresh Sleeve

Before Play:
Todd The Vinyl Junkie Vinyl-Zyme Gold fluid
Vacuum with VPI

Notes: don't go double strength on the Spin Clean fluid if you don't have a vacuum.

Also, you'll note that albums are vacuumed once before they hit the Spin Clean. You'll be shocked how much garbage still comes out in the Spin Clean vat. I'm thinking the Enzyme soak loosens the garbage in the grooves. The Spin Clean plus vacuum actually removes it.

Budget option: I get remarkable results using London Jazz Collector's DIY cleaning solution and a 3D-printed home vacuum attachment I purchased off eBay: 

https://londonjazzcollector.wordpress.com/for-audiophiles/home-brew-cleaner-for-vacuum-rcms/

https://www.ebay.com/itm/291452416779

I clean new & used records on an as-needed basis. 

Add Blue Sticky Tack for stylus cleaning (every 5 or 6 spins), dryer sheets, and an anti-stat brush, and you'll have clean records for a song. 

I first used L'Art du Son on my Keith Monks. Then I used Walker 4 Steps enzymes and the Keith Monks fluid for re-clean from time to time. After that I tried AIVS and liked it better than Walker especially for a less "dry midrange".
now I have bought a KLAudio but kept the KM (because I 😍 this machine). 
Now all my record collection is washed first with enzymes and second with ultrasonic.
Recently I bought again a bottle of L'Art du Son for periodic re clean and find it is best sounding when I make a final clean with it. It is not expensive and if you let the fluid for 2 minutes on the record it cleans really well. And more than that it makes music sound really good to my ears.

@mapman 

I came across this ultrasonic cleaner, reviewed by Fremer on his web site,  Analogplanet. Even though I have a VPI 16.1, I am considering one of these in the future. I really like the advantage of being able to clean 12 records at a time. The price is considerably less then other ultrasonic on the market, and you can purchase options/attachments separately.