For no-lamp gel-effect polish, the basket can be very small: one colour, perhaps a base coat, and perhaps a top coat. In the supplied catalogue data, many no-lamp polish examples show strong discount signals and low individual bottle prices, including options from Max Factor, Sally Hansen, Rimmel and Essence. Those signals can make gel-effect polish appealing if you want to try several colours without committing to equipment.
For UV or LED gel, compare the total setup cost. A starter kit may include a lamp, base coat, top coat and one or more colours, but kit contents vary. A cheaper kit is not automatically better if it lacks essentials you will need to buy separately.
When comparing products and offers, look beyond the headline saving. Check bottle size, whether a top coat is included or required, whether you are buying colour only or a full system, and whether the shade is one you will actually wear. A large discount on the wrong shade is not good value.