Is $5,000 to replace 4 windows (5 units total) with Milgard windows a fair price?

I have 4 windows, technically 5 since 1 is a radius on top of a rectangular window, that need replacing and just got a quote. I'm just seeing if this is fair for the Southern California area. They're pulling that "we can only offer this today" rate. They initially said it was $13,000, if I signed today it was $9,500. I said no, they called and said they had a bulk order and they could put mine in with it and now the price was $5,000. I'm assuming this is also just a scummy sales tactic but just wanted to see what others thought about the price. I'm definitely doing more research but it's a bit late in the day to try to get a second quote to compare. That's my thoughts exactly, pretty dishonest with their sales practice and trying to rush me into committing to their sale. I'm not really in a rush to get the windows done anyways so I'll shop around.