They won’t even talk discounts until you are fully approved to buy and have handed over a check for deposit ($2500).
That’s the oddest thing I’ve ever heard.
I haven’t left a deposit for a new home until we’ve agreed upon the price.
If they DO require you to leave a deposit, I would only do it at the time you make the offer, and then only if you get IN WRITING that the deposit is fully refundable if the offer is not accepted.