What kind of maintenance should I do on a 2012 Prius V

Have you looked through the Warranty and Maintenance Booklet (see attached)? Toyota USA spec's a schedule in there. In addition, I'd consider:

1. Full clean out of the EGR (Exhaust Gas Recirculation) components and intake manifold. With the latter pay close attention to small diameter passageways, at each port; they are the last leg of the EGR circuit. More info:

Bad Flywheel | PriusChat

You're DUE for this, and Toyota doesn't want to know about it, is basically hiding their head in the proverbial sand, hoping to keep owners in the dark, complacent. Until head gasket failure rears it's head. Neglected EGR inexorably clogs up with carbon, first to completely clog is invariably cylinder 1 (at passenger end of engine), engine runs hotter, head gasket starts failing, and you get get coolant consumption, possible hydrolock on piston 1.

2. Have the brake fluid changed. Toyota USA says nothing about this, while Toyota Canada says every 3 years or 30K miles (48K kms actually). There is a non-Techstream method for doing this, see attachment for details.

3. Change transaxle fluid. It's a simple drain-and-fill. Dealership may try to tell you otherwise, say it isn't necessary, and on and on. I'd strongly recommend to only use Toyota ATF WS fluid. It comes in quarts/liters, you'll need 4. Also you should replace the drain and fill bolt washers. Toyota recommends to only use the ATF WS from freshly opened bottles, and to not store leftover; just recycle. More info in attachment.

4. This IS on the official schedule, but it seems dealerships and owners enable each other in neglecting this: an in depth brake inspection. It's supposed to be done tri-yearly or 30K miles (same as Toyota Canada says for brake fluid change), but it seems like everyone just ignores this, relies on the "visual inspection" that happens every 5K or 6 months miles, basically in conjunction with tire rotation.

For the oil burning issue: how often are you changing your oil? 10K miles or yearly? I'd recommend 5K miles or 6 months instead. Also consider an oil catch can install. More info: Oil Catch Can, Eliminate that knock! | PriusChat

For pretty much all of the above, watch @NutzAboutBolts videos too, they're linked in a thread pinned at top of 3rd gen maintenance forum.

 

Frequent oil changes may help the oil burning which "usually" does not show up at the prospective car's mileage. However it is no guarantee because the factory had a defective piston and ring design that were not updated until 2015. The ring design was so bad some were replaced under the original 5 year 60k warranty. However almost all 2012-14 v's are original and oil use after 150k can be expected.

So if I had a choice, I would buy a 2015-17 v based on this factor alone. The egr is also a bad design but was never fixed on the v wagon. It was redesigned for the gen4 standard liftbacks by 2016 but not on the v.

The 800 pound gorilla for the early v's and liftbacks is headgasket failure that can sometimes take out the engine.

Finally, keep in mind that the abs/brake booster and the inverter were poor designs as well. They have an extended ten year warranty (customer support program) which on a 2012 expires in late 2021 or 2022 depending on original purchase date. So make sure the deal you get on a 2012 v is great.

 

Yeah read the attached warranty an maintenance booklet; the biggie at 100k or 10 years is engine coolant change, and inverter coolant is at 150k or 15 years. Plugs at 120K or 12 years.