Or is copper piping the better choice?

Sure, there are people that don't have a choice, but for those who do, they will just wait until the Spring.

But, when you need to know to make the choice you can make some assumptions  that you can evaluate as you go.  

If you want to operate as a charity that is your choice but if you are a business and the business says tenant pays then the tenant pays.

There are several markets in the Midwest that have homes in rentable condition for $30,000.If you can find a lender to work with you,  that opens up your choices, but many investors have been happy in Indiana, Tennessee, Missouri, ohio, etc.  

Now that she see its a career choice and I speak about it with passion,  she embraces it.

If you have a unit where it is prohibitively expensive to do it that way or it would be tiny you could go with a shower but it would not be my choice.  

Do I get choices?

It's a choice.

Call this what it is:  A personal life-style choice.