Hi Sherley. I hope one of the New Jersey real estate professionals will answer your question as they would know if your idea is ok in New Jersey. I know some states don't allow rebates, but it doesn't sound like you are offering a rebate.
Anyway, why do you think you should pay for repairs or other things out of pocket before escrow closes? Why would you invest in someone else's property just to get their business. You'll be out that money whether the property sells. What if you pay for repairs or staging and then they cancel the listing agreement prematurely. Of course you can make the cancellation contingent upon them paying your out-of-pocket expenses, but I can guarantee you that they won't be happy if you actually follow through with it.
My suggestion to you would be that you offer to pay for certain things at the close of escrow (I have offered to pay for the pre-inspection termite report at COE or the appraisal), but I won't pay for those items if escrow does not close. By offering to pay you also make it look like you are desperate to get their listing.
My advise is, if you feel you have to make a contribution, do it when escrow closes and you have a commission to pay it from. You'll have plenty of opportunity to spend your money during the listing period because you'll have to spend at least some money on marketing the property. You need to lead by revenue (i.e., don't spend money that you have not yet earned). I would highly recommend that you read the Millionaire Real Estate Agent (co-authored by Gary Keller, co-founder of Keller Williams Realty).