is there a limit on builder incentives for investment loans?

I went under contract with a new construction townhome in South Carolina.   The deal is good and the builder offered 10K in builder incentives as part of it.  The mortgage guy told me there is a cap of 2/2.5% on builder incentives for investment mortgages.  So based on that, I would not be able to realize the full 10K incentive.  Also, they wont budge on lowering the price any further.  I have tried researching here and elsewhere to get confirmation of this but cant find anything that says there is a cap.   Anyone know anything about this or have any ideas to get around it?

Thanks