Power Steeing- wheel is hard to turn

First of all, I'm not knowledgeable in car mechanics at all. Steering in the Kia at some point got hard then unable to turn at all. Took it in to a mechanics was told two hoses were leaking and rusted out. Had them replaced for about $400. When picked car up was told it would be hard at times for about 2 weeks until all the bubbles got out of the hoses.

Three weeks later when turning it will be extremely hard and then mid turn it will loosen completely almost making you run into things. Not all of the time does this happen, but I notice as I drive the car more throughout the day it becomes harder to turn with every turn.

Brought it back to the mechanics today and was told maybe its the pump will need an additional $200 and a used pump can get put in.

I don't think I want to waste my time with the mechanic anymore and need some help if possible. Any suggestions?