$30 for remote start? Will it work on Prius? I do not know. Looked like a good price to me. Ready Remote 24926 Deluxe Remote Car Start System w/2 Remote - 24926 - Buy.com
I'd be scared to death. Although most remote start applications live or die by the installer doing the work.
Actually, it probably would work. But you'll also need an immobilizer bypass that works with the Prius. Check the Gen2 threads for that discussion. If you find an immobilizer bypass that works with a Camry Hybrid, it will probably work with the Gen3 Prius. As chrisj428 says, the installer makes all the difference. Several people paid $800 for Gen2 installations that worked, and many others paid less for disasters.
The stock remote (that only comes on package IV ... but can be factory installed on Package V as well) costs a lot more, so I'd be reluctant to guess that it'd work. .