I've never heard of Star San, but you answered your own question with the hot water/soap/isopropyl alcohol/ultrasonic cleaner =]

When cleaning my glass bottles i wash them in a SS bowl of hot soapy water, then i rinse them off and rinse them again in distilled water. I then air dry them for about an hour at which put i put them in the oven at 170 degrees for a half an hour. I do the same for all the SS items i use.

I'm a friggin' slob compared to other DIYers. I have a coffee cup I iso wipe every couple months that I store my syringes in. I have one syringe that is OG and that's what... 9 months ago? I rinse with distilled water 5x no matter what went in the syringe. I wipe with paper towels and iso alcohol before mixing.

I have noticed absolutely no growth, dirt or other shit I wouldn't want to inhale. PG seems to be more anti-microbial than I thought at first, I just figured it was sort of neutral, where VG would be like an agar. I'm still not too sure about how clean you need to keep the stuff with VG but I just keep it capped and "pour to final volume" the VG with my stuff, I don't measure it with a syringe.

WAY dirtier than what would make clean beer doesn't seem to matter with DIY ejuice.

edit: Oh yeah, I 10% vinegar soak my used HDPE bottles when I actually clean 'em. Most of the time I just put the same flavor back in.

edit again: I mix in the 85vg/15pg range

I never use anything that isn't food grade. Get yourself a bottle of high proof grain alcohol, such as Everclear. It will be all you need for keeping stuff clean, aside from washing grime and stray bits of PG/VG off of utensils.

I don't think you could grow bacteria/fungi in ejuice if you tried. It's still important to keep things clean though, because you are inhaling this stuff.

No need for anything other than boiling water in my opinion. I boil in distilled water, but I'm sure tap water would be OK as long as you give it a distilled water rinse when you are done boiling. Hot bottles and tools will dry off very quickly after boiling.

Former brewer here also!

Sanitation in making juice isn't too important in my mind - as long as you're mixing in a clean environment you shouldn't have any problems. I treat it the same way as I would preparing food.

Yeast and bacteria can survive in VG but they won't reproduce. VG is often used for storing yeast below freezing temps. As /u/meshman says PG is antimicrobial.

Starsan would probably be OK but I think it's a bit over the top. Even though it's a no-rinse sanitiser for brewing I'd be inclined to rinse it when making juice. I think the ratio of residual sanitiser to finished product would be a little too high when making relatively small quantities of juice.

I do what /u/SumDudeYouKnow does for cleaning. Hot water only. I would consider using food grade alcohol but more so to remove residual flavour than to sanitise.

I think the combination of the PG and heat from vapourising should be enough to keep any nasties at bay.

PG is anti-microbial. Nothing should be able to live in it. I would avoid cleaning with soaps.

I like unscented bottle soap. It's made for cleaning baby bottles but it works great for all my DIY stuff. I do a thorough cleaning then rinse one last time with distilled water.