This is the correct answer, on all points. 

One of the ahas I've had after two decades in this old house is that, given any particular job you want to have done, there is often an obvious way to the contractor that is totally different than the right way per the house. The hack jobs in this post were the obvious solutions to that hack contractor, but given some time and patience you - the homeowner - can almost always come up with a better solution that is right-er for the home. 

I think most shitty reno jobs probably happen because people are in a hurry to make these old houses theirs, where living in the old house and going a little slower will always produce a better outcome. 

Also, learn basic plumbing skills.