I want to thank everyone for sharing their experiences and knowledge. I'm an overthinker, so the more input I get the more satisfied I am with my solution. I posted a link earlier in this thread to a website where someone made a 4'x4' brooder from plywood, with 1"x4" framed hardware cloth for the top. The brooder will go in the garage in a corner protected from drafts. This seems safe and secure, and plenty large enough for my 6 chicks to get their start until it's warm enough here to transfer them to their house outside. I like it especially since you can easily break it down for storage in a limited amount of space since the brooder just slides together without any fasteners.
I purchased a Brinsea 600 heating plate for heat. I've checked the temps in our garage, and the lowest it's been is 50 degrees, so the heat plate should work fine since it's warming up here every day. I've purchased a chick waterer and a chick feeder, as well as a larger waterer and feeder for when they graduate from chick size.
I've just finished up the brooder and a pic is attached. I've purchased a coop, and I will start assembling that soon. I hope to get my chicks in a couple of weeks. Again, thanks to everyone who took the time to reply to my plea for help. I really appreciate your taking the time to help me!! I hope to be able to pay it forward as I learn the ropes!!