Hello and welcome! Perhaps your best advantage to negotiating is knowledge. You can use this site's search feature to look at other threads for new builds. Knowing things like, electrical requirements, pump size, preferred filter (sand, cartridge, etc) type chlorination (SWG or liquid chlorine), decking type/size .... it goes on & on. If you have some specific parameters you would like to share with us for feedback, by all means please do so. Forum members will gladly give you their 2-cents worth, then you can take that back to the contractor(s) for consideration. Welcome to TFP!