Well, how handy are you? If you're the kind of a person who, say, works at a Toyota dealership as a service tech, all of those are DIY.
If you don't have so much as a screwdriver at home, you might have a hard time.
The "Low oil pressure" light, on most cars, isn't so much a "low oil pressure" warning as "no oil pressure." I'm quite surprised the engine didn't seize up, and there's a good chance that you did catastrophic damage to the motor with that stunt. That's a "Shut down, NOW!" light on the vast majority of vehicles out there. Usually it's low oil level, but not always.
Three hundred miles with that light on? Does it sound like a bucket of bolts when you start it now? I'd expect damage to the main bearings, and probably totally thrashed rod bearings, though admittedly I'd also expect a seized motor or a windowed crankcase (as in, the engine throw a rod through the side and made a window) for that sort of abuse.
Does it clatter if you rev it up and let off the throttle when warm? If yes, you're looking at a total rebuild.
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That said.
I think they forgot a few things on the list. You're missing a muffler belt replacement, they aren't topping off the blinker fluid, and I think your turbo encabulator bushings are due for service too (those are all junk service items that don't exist).
A/C belt replacement: $133
That's probably the serpentine belt, which is likely a $50-$70 part. How hard it is to replace depends on the vehicle, but it's often quite the pain.
Spark plug replacement: $222
Really? Wow. A set of plugs is about $40 (iridium tipped), and it's a pretty easy service. Looks like maybe half an hour if you've done a limited amount of car work before.
Fuel injector cleaning: $173
There are two kinds of fuel injector cleaning: The worthwhile kind, where they pull the injectors, usually send them somewhere, and do a reverse flow ultrasonic cleaning bath, balancing, blueprinting, etc. And the worthless kind, where they slop some liquid in the fuel manifold and in the fuel tank and it might make a very minor difference, but not much.
My guess, based on the rest of this, is that you're getting the worthless kind, for a nicely inflated rate. You can toss some SeaFoam in the fuel tank for a lot less money, though, and accomplish about as much.
Transmission flush: $247
This is a thing, though unless you've burned up the old fluid badly (it will be black and smell burned), there's no good reason to (and, if you've fried the fluid that badly, the transmission is probably already toast). If the fluid is in good shape, especially on a Prius transmission, there's no reason to do this. Replace the fluid if you want, which is messy... if it's in bad shape.
Engine coolant flush: $220
See above. Just replace the coolant if it needs replacing. Drain and fill. Probably $30 of coolant at your local parts store.
Brake system flush: $173
"Bleeding the brakes." Probably needs to be done, but $10 in brake fluid, a vacuum bleeder, and a jack lets you do this. I have no idea what sort of nonsense you'd need to be doing to pay $173 for this.
Upper radiator hose replacement: $595
Lower radiator hose replacement: $311
Apparently those are a genuine pain to replace, but unless they're showing signs of swelling or cracking, probably not needed. The issue is apparently that it takes forever and a day to bleed all the air out of the system properly. That's... still really, really high, though.
Alignment: $124
That's fairly reasonable, though I doubt they'd actually do it if you took it in for it, given the rest of the list.
Brake cleaning/adjustment: $85
... I don't even know what that is. Lubing the caliper slides, maybe? I'm guessing they'd find you need new brake pads while you're in there.
I listed this all out on PriusChat and their recommendation was to continue to monitor my oil consumption and performance for a while before committing to any of these repairs since I drove on low oil pressure for quite a while. My question to the forum is what can I realistically do myself with little experience, what must be done, and what can be deferred?
First, you need to find a better shop. My gut feeling is that they're bending you over, badly. I wouldn't pay that for most of the service, but then again, I have rebuilt engines. So my skill level is definitely higher.
You really should get someone who knows what they're listening for to listen for rod knock after running that far with low oil pressure. Oil consumption isn't the concern, it's the bearing damage. If you've got bearing damage, it's not worth throwing any more money at the car unless you're attached to it, because it's going to need an engine rebuild (at which point someone will do most of the other work listed anyway).
Otherwise, do you have car-handy friends? I'd be comfortable helping someone out with an awful lot of that, but most of my friends also work on vehicles, so wouldn't need much in the way of assist on that. They might reach out to me for the battery pack, since I work on battery packs a lot.
Look for a local import shop and see if they agree with most of that. Unless your car is nearly ready for the junkyard, that list is a load of inflated nonsense.
