I do the following on my portable. Some might see it as OTT but if you look after stuff it will last for years and it soon becomes a habit so I do it as a part of my working day. My back up Alltec twin vac is donkey's years old but still looks good and is in good working order.
At the end of and during each job.
Machine gets a quick wipe, check vac stack filter/s for debris and wipe recovery tank lid. If i'm using envirodri I take brushes out and clear. Damp wipe any other machines i've used as I put them away, Vacs are run as I pack away, Machine in last if it comes out the van.
Daily.
This is one operation. I hook up solution hose then use my priming hose (or open ended hose if you like) on the end and run cold water through the pump and hose, I vent this into recovery tank and flush all the crap out and dry. Nothing worse than a smelly tank. Then run the vacs for 5 - 10 minutes. wand gets a quick flush too. Wipe other machines in use that day. Sounds time consuming but only takes 15 - 20 mins and means when I turn up for the first job in the morning it's all ready to go, clean and tidy.
Weekly.
Machine opened up and check for leaks, obvious faults cables etc. Wipe the interior of any dust and just ensure it's all working as it should. Check mains cables/plugs on machines for damage. Give machine body a good clean then spray quick connectors on machine and solution hose with silicone spray. Same with machine body. Check all the tools/hoses for signs of leaks or drips and make sure jets are clear and aligned right. At the same time van gets vac out and a wash and restock any items that are low. Again takes no more than an hour or so.
My van is racked out and everthing has it's place so it's easy to keep tidy and easy to spot anything missing so I don't often leave stuff behind, customers often comment on it too so they do have a look when your unloading or loading up.
Machine Serviced/pat tested as required