Newsflash: How to negotiate on a new build?

Looking to potentially start constructing a new build.Info:Base price+ options: $667kAvg design center spend for neighborhood: $45kLot premium: $16k Total: $728kCurrently builder is offering a finished basement rec room incentive valued at $23k given to all home buyers in the neighborhood , and an $8k design center credit the agent offered us right off the bat without asking to help offset lot premium cost so total as it stands is $720k. I have been reading some old threads on how people building new constructions have gotten additional things thrown in after the initial offers/incentives like additional design center credits, waived/upgraded lot premiums for free, or included options like cabinets/kitchen appliances, also closing costs covered if using their lender. We understand base price won’t reduce as they don’t want to set a comp precedent so what do people view as the best approach to trying to negotiate the mentioned perks? We really want to be at $700k all in (Also for reference the lot premium is crazy to us as the only benefit is it’s a south facing back yard but besides that it’s the minimum lot size and backs up to another home and the lake facing lots are a LOWER lot premium at $15k)