Sara, as a professional make-up artist, has a 40% discount on all makeup products at a store.
Is it permissible for Sara to purchase items with her discount lechatchila in order to then “re-sell it” to her sister Rivka at the same price (i.e. 20% off) or is this considered gezel?
Is there any technical difference if Rivka gave her money to buy it for her in the first place?
This would depend on the stores policy in giving discounts. While it is clear the intent is for her to buy for her practice and not resale, many stores are happy to leave open these “legal loopholes” which increase sales and revenue and don’t harm their retail sales. Especially if it is done a one time basis and not consistently. However some stores do stipulate that the sale is for professional use only. The stores policy should be clarified.