C1256, C1300 codes. Actuator buzzing and loud beep w/ lots of dashboard lights on start up sometimes

I have a 2009 prius.
First, I hear a buzzing noise from the front of the car that repeats over and over again even when I turn the car off, which I believe is the brake actuator. It has been getting more frequent over the past couple months and lasts quite a bit even after turning off the car.

Second, the past couple weeks occasionally when I start up my car, I get a loud BEEEEP and a bunch of lights on the dashborad light up including the ABS and red triangle. But after about 5 seconds, it stops and all the lights turn off and the car drives as normal.

I took it to an automative shop who used techstream to get codes and got the C1256 (Accumulator Low Pressure) and C1300 (ABS ECU malfunction). The quote for replacing the ABS was about 2500 using a new Toyota OEM part.

The price seems to line up with other things I've found online, but I was wondering if it could possibly be another issue like the skid-control ECU just needs to be replaced or a battery issue?
I am hoping if y'all could provide any suggestions of what I (or the shop/dealership) can test to make sure it really is the ABS problem or not?

Thanks!

 

It's a 2009 Prius Gen 2 with 211k miles on it. I've gone to a local auto shop and a toyota dealership to get a diagnostic and they both said I would just need to replace the ABS. The local quoted it at 2500 while the dealership quoted 3300. Because it's so old, I am considering just buying another car instead of replacing the ABS.
How would I do a 12V load test? The dealership said the battery had no issues, but I'd like to learn more about cars anyways!

 

I see, I may just bite the bullet and a buy a newer car. It's just the cars I can buy are very old and high mileage anyways (I'm a college student). Thanks for your help.

 

Would you recommend one that isn't hybrid?