Jeep Cherokee Air Conditioner Hose

I Am Thinking Of Buying A 1999 Jeep Cherokee And Noticed That There Is Some Rust On The A/c Hoses, On The Engine Block, And On The Valve...

I Changed The Lower Radiator Hose Recently After It Burst. Since Then The Temp Needle Will Creep To 220 Then Shoot To Redline, After I Turn...