I plumbed a low pressure propane (we live in the woods not city) into my garage
years ago and love it. It's not rocket science. When brewing off of the house gas line, you do not need a regulator, it's already regulated. I use a furnace valve and PID to auto regulate mash temps when I continuously recirculate. At first I just used a needle valve on my banjo burner, which worked great. Depending on which type of propane you use (propane/natural gas); you will need to drill the appropriate size hole in your gas jet. Again, not rocket science. Just keep opening up the jet hole size until you have sufficient flame. I brew in my garage and just crack the door some when heating. I installed a gas valve next to the garage wall with an acme quick connector for the brew rig and smoker. I have a relative who is an insurance agent (ya), she stated that in the event of an issue; insurance companys would have a greater issue with a propane tank being used inside a dwelling versus a hard plumbed black pipe gas supply line. Do a little research and for a couple of hours time and a little money, you will not have to worry about propane again.
As for co2 detectors; I'm one of those guys who doesn't ware a helmet and drinks water from a garden hose. To each his own.