As it gets used almost daily the chain (after each run), oil & lights all get checked each day's use.
Tyre pressure & tread depth, water get checked every 2/3 days. Chain gets oiled anytime it starts to look a little dry.
General look over each time it's cleaned with a deeper clean/polish each weekend and a brake pad check, chain oiling along with visual check of obvious bolts etc.
I'm averaging out at around 200-250 miles p/wk at the moment.
To date (from 2060 miles to 14000 miles) nothings come loose, lights have stayed fine, oil has not required top-up between changes and no water top-ups required.
Has just needed petrol, brake pads and tyres so far.