Business ProfileforSystem Pavers

I reached out to System Pavers over a driveway and walkway project. The sales rep came over and delivered his sales pitch. Now I knew that they werent the cheapest but I heard him out and he gave us a bid for for the project. It was higher then competitors but the work was warrantee for 25 years so we felt it was a solid investment and stood by their product. The price was presented and it didnt break down products and labor it was a magic number pulled from who knows where .. he wanted our business and did discounts to lower the price to a number we could manage. Now I signed the contract and we planned a date. The issue is that its a small project - under 450 sqft and they werent cheap for 45 bucks a sqft! So here is the issue - our faux wall made of wood fell so we decided to call our sales rep and ask to add 75 sqft to they project scope - to make up for the broken/fallen wall and complete the look of the project. Now I was told that he would honor the discount - that discount made the project 45 dollars a sqft this is high for competitors charge 17 to 25 a sqft but the promise quality .. so given our poor luck with the wall I explained out issue and that we want to add 75 sqft given that we were in bind the price we were given was 66 dollars a sqft I was surprised and asked why so high for such a small space and noted that his original bid / main contract was at 45 sqft after discounts and his response is that you cant go by price per sqft!!! Now lets be clear price per square foot is an industry standard that averages out the cost of materials, labor and profit... but the issue stands that we are already under contract and in need of amendment / add on the price per square foot is based on his sales goal for the month or visit !! And NO he didnt honor the discount because that would have been 45 a sqft not 66 ( a 21 dollar increase per squad foot ) !! Its ****** outrageous and smacks of exploitation of client in need once you have them!! Shady business!!!!