15k on a 450k-465k loan is not very substantial at all. If you get a standard 30 year load, that’s an increase of around $40/month. If you can’t afford another $40/month, then you’re stretching pretty thin @ $450k.
In regards to another $15k off, I don’t think it should be very hard to get. I know people who got $35k off last year and market was much better then than now. So, doesn’t hurt of put in an offer $450k if you really want Airoso @ $450k.