You NEED a service manual

It's the Nox sensors, take it to the dealer ASAP. My old truck had that problem due to. It keeping the def tank full. Running the def tank out dry will cause these problems and the urea will dry and cause def quality poor which will cause the p22a7 code. You have 200 miles of the warning light and then you will be limited to 55 mph and after another 200 miles 5 mph limiter. You will probably ether pay $1000 of fixing this issue that will return or pay $2000 and deleting it

The lines. you have 2.
high pressure and low pressure. combined, they cost around $400 at dealers but can be found cheaper online.
labor at a shop to replace both lines calls for 2.3 hours, so you will pay their cost per hour of labor.
plus shop fees and tax. (fees cover shop supplies like fluid, gloves, etc)
If the problem is the power steering pump itself, the average cost at shops for the part is $450 (part only) plus 1.6 hours of labor.

if the issue is the steering rack itself, you can find that part online for $350 on average.
If you just let the shop order the steering rack, they may hit you for $1,200-$1,400 just for the part, and labor times for that job is 4.2 hours.

Please note, the link I have attached may notbe the correct part for your toyota. You would have to search for the correct vehicle.
include engine size and other required info like "Toyota camry LE, 2.5L, front wheel drive"
Hope this helps.
2005 Toyota Highlander Power Steering Rack

parts vary from dealer @ $400 to junk yard @ $50
labor rate = 1/2

therefore you will pay 1/2 what ever the garage charges per hour PLUS the cost of the part

however, the garage "charge" for the part is generally twice the cost of what you pay

this is because when the "new" part fails they have to install it for free if under warranty

if you buy the part yourself... expect to pay no more than one hour service time usually less than $100

Tell them to show you the LABOR RATE MANUAL they are using to explain how many hours you will pay for job, multiply that by the LABOR RATE plus parts costs . Some jobs are labor intensive. Check it out. Hope this helps

The labor shouldn't be more than two hours and the part should be around $75.00 max. So moderate shop will charge $95.00/hr for labor, a dealer closer to $125/hr. So at a cheaper repair shop, $265 plus tax, at a dealer more like $325 plus tax. Its an important component, but you don't have to get it fixed at a dealer. hope this helps
paul
P.S. Pep boys has cheaper labor and good mechanics.