Does anyone know anything about hair extensions?

hey, ok, well im thinking about getting hair instintions, and I was just wondering about these questinos, cause I've never had them before, and im hoping I can get some answers.

1]] How much do they normaly cost, I know someone said it depends on how long, and everything, well I want mine pretty long. Give me the price range.

2]] Do you need to keep going back to the salon? Like do they fall out? or do they ALWAYS stay in?

3]] Can you dye them like normal hair?

4]] Do you wash them like normal hair?

5]] Does it hurt when you have them??

ANYTHING ELSE you CAN COME UP WITH WIL BE SOME HELP! please and THANK YOU <33

this is what I want the hair to lok like

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