Cost of plumbing reno in Mesquite, TX???

[Jairo Munoz]

Hi community,  this is my first post here. I am adding a 1/2 bath and replacing a 3" cast iron pipe under my 1400 sq.ft., pier and beam house thatim renovating. A plumber quoted me $6600 to replace all the plumbing including the cast iron underneath the main bathroom.  Is this a fair ballpark price?? Materials are included and job will be permitted with the city. The job is start to finish. 

Any other recommendations? This was my first quote from a plumber .