General questions about Geckos

Question
Hello mam!!
I live in India and love lizards of all types, especially geckos (House lizards that are crawling on the walls)
I want to know some general things about them.

1. Life span of the average house lizard
2. Are they poisonos to eat??  (This is just a general question, I m vegetarian, I just want to know. I wont eat them)
3. Why do geckos living in different parts of the house have different colours?? ( Like the lizards in kitchen are creamy colored, but in some other places the are dark and patterned)

Thank u!!

Answer
Namaste! (I hope I spelled that right!)

 Depending on the species, the house lizard can live an average of 8-12 years.
 The only poisonaous lizards are the beaded lizard and the Gila monster and they both are native to North America.  Some do have a mild poison as a defense mechanism if an animal tries to eat it, and some others are food animals for humans, such as the iguana in Central and South America, and several lizard species are consumed in Australia.  Also the American alligator can be used for food.  As far as the house lizard, I've so far not found anyone who has tried them as a meal.
 Most reptiles have the ability to change color to absorb or reflect sun.  They get darker to warm up and lighten when temperature is reached. Once warm enough, they will start hunting and eating any insects in the house, which is why they are wonderful to have.  I would guess they find insects often in the kitchen so they bask in the sunnier portions of the house or just outside, then keep your kitchen insect free once they are warm enough.