Both Dawn & Simple Green are for removing dirt & debris- either from dishes (Dawn, which is also used for cleaning wildlife that's gotten into petroleum oil spills, incidentally) or from household things (in the case of S.G.). Neither one is a "disinfectant". But just mild soap & water, cleaning thoroughly, is often enough- you need to clean first, or the dirt (feces etc) actually deactivates most of the disinfectant ability of other products used. And if you don't follow the directions when using disinfectants, they might not be doing all that you imagine anyway. (Most need to be left on for 10-20 minutes before wiping dry for maximum effectiveness.)
Any soaps, Dawn included, do need to be thoroughly rinsed from reptile homes & accessories. That's one reason many of us like to use a convenient spray-on disinfectant (such as chlorhexidine or F10) that doesn't require rinsing- only drying. But remove the "dirt" first.And if you can't afford a disinfectant, just a thorough regular cleaning with "soap & water" is probably enough, especially if you aren't keeping large numbers of reptiles, adding new ones all the time, or breeding them- AND if yours appear to be healthy. It's another matter for vet clinics, pet stores & breeding locations- disinfectants are a "must" for them.