It will be difficult or impossible to remove the pan and leave the walls in place, since the wall treatment is installed over a lip on the edges of the pan.

You need a contractor who can remodel bathrooms.

At least the lowest row of tile will need to be removed and replaced.

An experienced tile contractor.

Go drive by Home Depot or Lowes and get two illegals that speak some English. Get some boxes to put the waste in so you can put it on the curb or take it to the dump. Many trash pick up companies won't take "construction waste" so put it into boxes, tape them up and put out over several days.

Look on craiglist under labor. There are often people who offer demolition & haul away services.

An experienced tile contractor may also be able to do it, for an additional fee.

I live in New England, and I've not been able to find day laborers outside the home improvement stores.

If you use someone besides a tile installer be ready for additional tile work.

A tile contractor should be able to remove the lowest row of tiles (unless the backer is inadequate).

It does take some finesse to get the bottom row out without damaging the higher rows.

Having whomever is going to replace the base perform the removal would be a good idea.

"Whenever you want a contractor, get only licensed contractors for your repair work."

Licensing rules depend on the state.

Not all specialties require licensing in every state.