Wood treatment? And paint in the compost? What are you talking about.
Sure if cost isn’t an issue worm 360 is an option also.
But for a easy DIY for about $25 usd vs Worm Factory 360 for $130 I call it a win
Good on you for wanting to vermicompost as soon as possible!
My sis used a DIY Rubbermaid bin for several years. She generally treated it in two zones, left and right. She'd put down kitchen waste in the left side, and the worms would sort of migrate there. For the next trip, she'd put it down on the right side.
Her most frequent complaint is that the worms wouldn't leave the old zone for the new zone. (I find this true with our vertical bin also, to a certain degree: worms will migrate up to the fresh food, but many will remain on the lower levels until the food is completely consumed.)
We live in an apartment, and use this worm bin in our utility room.
Rats are a whole different issue. They're devious, capable, and smart, though I'm not sure that shredded compost would be their first pick for food. You could make vertical "stilts" to hold your bin, or you could suspend it from the ceiling. Rats are smart as hell though, and will likely figure out how to bypass any protective measures you put into place. Deal with them, and vermicomposting will be easy. If you're in an apartment, the landlord should provide pest control services.
Also, if you have a blender, consider getting one or two big, regular (not wide-mouth) mason jars. We generally have 2 on the countertop. Edible/tasty kitchen trimmings (ends of onions, celery greens, ugly but non-rotten bits of carrots, bell pepper piths, meat trimmings) go into a freezer bag for making broth later. Inedible stuff (used coffee filters, tough asparagus bits, wilted flowers, pinched-off ends from growing plants, that bit of the carrot that includes the remains of the green part) goes into a Mason jar as future worm food.
The recommended ratio of brown matter to green matter is 60% (brown) to 40% (green.) It's often a challenge getting more brown matter than green, since most kitchen waste is green. We have a paper shredder (crosscut shredder, $7 from Goodwill thrift store) and I bought a big brick of coconut coir from Amazon. Peat pots whose seeds don't germinate also go to the worms.
Good luck!
I’ve just received my order of the DE. Was curious if you could recommend how to use it? Where to apply and what amount. We have a 360 worm factory: https://www.amazon.com/Worm-Factory-WF360B-Composter-Black/dp/B002LH47PY