The cheapest ones are around 12 bucks (10W no plug). The DL is that they come in wattages increments of 10. There are warm white, white and cool white spectrums, Color chaniging (RGB) via remote, and pure actinic that I have seen, most of them are sold with a cord that has no plug (DIY the plug, there is a thread on here for how to do it-somewheres)-some do have a US grounded plug though, but they cost a bit more. There are various reflector styles out there, some with 2 clusters of LED's, Most with SMD led, some with CREE(more $$). every 10 watts yields about 800-900 lumens.