Because Nails Inc is not included in the supplied product candidate examples, it would be misleading to make claims about its current prices, discounts, bottle sizes or retailer spread here. Instead, use the Nail Products listings to compare like for like at the point of shopping.
For Nails Inc, look first at whether the listing is a colour polish, a treatment, a kit or a nail decoration product. Then check the bottle size, shade name, finish and whether any offer is attached. If you are comparing it with Sally Hansen, make sure you are not weighing a premium-looking colour polish against a practical nail treatment and calling one better value purely on price.
Nails Inc may still be the better buy for you if the available shade, finish or set format suits your routine more closely. Value is not only the lowest price; it is the best match between what you will actually use and what the listing offers.