I sit back a lot on here and let the shop bashing go on without saying anything most times but I gotta be a dick on this one.
So a shop with experienced installers who do these jobs on a daily basis and have the training to deal with any problems that come up knows less about doing this and will do a poor job conpared to you who has no idea what to do, where to start, let alone trouble shoot anything. We are in business for a reason and work on vehicles daily with no damages. Why not trust a shop? If you don't trust the installers at your local shop you need to find a better quality shop. Remote starts and alarms are not something to be taken lightly. There is a lot that can go wrong while installing one if you don't know what your are doing. How are you planning on testing your wires? DMM or a test light? Or are you just planning to trust that the tech info you get is correct? One wrong wire or grounding the wrong wire and kiss your bcm, ecu, or airbag circuits good bye. That will cost you a lot more than the $100 to have it installed. Let alone a shop will charge you just as much if not more once you get halfway through it and relize you are in over your head.
Sorry for the rant, but I have had enough with the shop bashing. Yes we are a business, that means we exist to make money. We do that through selling products at the prices the manufactures tell us to. We charge what we do for installs because we have rent to pay, lights to keep on, and the installers have families to feed. Keep that in mind.