We agree that removing a ceramic tile floor can be a difficult task, however we are quick to disagree that it must necessarily be an expensive one. On the contrary because this work usually doesn't involve unusual skill or training it is something that, with the proper tools, most homeowners could perform in their spare time. If do-it-yourself is out of the question here then the work can be performed by a local handyman or small repair contractor for a modest sum.
Chances are that since your home is built on a concrete slab the tile was installed using a thin set mortar. This is nothing more than a cement based adhesive that is used to join the tile to the concrete floor. Considering the vast area involved we suggest that you use an electric floor scraper to remove the tile. This devise, available at most tool rental establishments, has a scraping blade that reciprocates back and forth breaking the bond between the tile and the slab. Any mortar that may remain once all of the tile has been removed may be eliminated with a once over sanding with floor sander also available from your local rental center. More then anything this is a messy job that requires a little patience and a lot of elbow grease. Be sure to wear protective eye goggles and a dust mask over your nose and mouth.