Determining plumbing rehab costs/loan for foreclosed property

[Ned Shuck]

Anyone have suggestions on determining plumbing costs for a winterized single family foreclosed home that is requiring a rehab loan because of plumbing, but isn't giving any info. on the actual issue? I'm not seeing any structural issues/water damage. Do I just need to bite the bullet and pay for an inspection, then pay for a contractor to come out and give me an estimate? I'm not sure how all of this will affect my offering price. This will be a live-in flip.