Have you lived before this life?
For me, the answer is a resounding yes!
Here are some of my experiences.

Where are you?  "I am outside, it is very warm and the sun is shining."
What is going on?   "I am in the market place buying fruit for my master."
Who are you?  "I am a slave.  I work for an old woman who owns me."
Are you wearing something that says you're a slave?  "No, why would I be?"  Are you allowed to move about freely?  "Of course I am!  How else could I do the shopping?"  How do the shopkeepers treat you?   "With courtesy, if they want me to buy anything from them.  They treat me like they would anyone else."  Can you run away?  "Of course I can just walk out of town, but then where would I go?  I'm very happy here.  The old woman has owned me since I was a child.  She taught me to read and fed me well.  We're friends, she can't take care of herself properly without me, why would I leave her?"  Don't you want your freedom?   "Slaves move about like any free person here.  There is desert all around us.  We are treated well.  There is no reason to leave.  I am happy here, I like my life."
What are you wearing?  "I am wearing a light blue robe, I am barefoot and  carrying a woven basket."   What color are you?   "I don't know." Look at your arm.  "Oh, I'm brown."  How did you become a slave?  "My mother and I were captured in the last war." What do you do for your master?  "I do her shopping, cooking and cleaning.  I help her take care of herself and her home.  I also read to her." You read to her?  "Yes, of course, I read to her.  She loves to have me read to her.  Especially at evening when she retires." You can read?  "Of course I can read!  Who couldn't read?  Even four year olds can read!  Everyone reads!"  What do the houses look like?  "They are made of mud with poles sticking out from near the roof.  The roof is flat."   Go to the end of this life and tell me how you die.  "I just leave my body.  I'm old, but not as old as the woman who owned me."  Why do you die?  Are you sick?  "No, my master has died.  I lived a while after that, but I'm bored.  It's not the same without her.  She was a good friend.  There's nothing much to do and I'm bored, so I decide to leave my body and go on to the next life."

Where are you?  "I'm in a cave."  What are you doing?  "I'm preparing to go down to help the villagers with a ritual."  Are you male or female?  "Female"  What color are you?  "A beautiful golden brown."  Is this how you make your living?  "No"  How do you live?  "I kill, I eat."  What are you wearing?  Nothing.  I don't wear clothes, the villagers wear clothes."
Then you are naked?  "I'm not naked.  I have my fur."  What do you look like?   "Like any of my kind.  I have long corner teeth that go below my lower jaw.  I am a beautiful golden brown.  I am one of the most beautiful of my people.  I have a long tail which is a little darker than my coat.  My back is slightly darker too.  I am a great shaman and hunter."  Then you are not human?  "I am not human.  I am a great cat.  I am what you would call a mountain puma."  You don't eat the villagers?  "Heavens no, I'm not a savage.  They probably don't taste very good anyway.  I'm a shaman.  I help the villagers do ritual and I teach them."  What do you teach them?  "That all are One and there is no difference between us, even though we look and act differently.  I also teach them to ask their intended food if it is willing to die for them, and that they must take its spirit into their own.  They must not take unwilling food or they degrade themselves."   Are there any large cities around?    "I don't know what you mean.  There is a human village in the deep forest near here.  There aren't any other human settlements close by here."  Are you alone in your cave?  "No.  I have a little mouse I talk with every day."  Do any other animals help the villagers in this way?  "Yes, there are many of us who do this for humans.  All kinds of the non human people, what you call animals help with ritual." Go to the ritual and tell me what you see.  "The villagers are assembled and the baby is on a robe on the rock."  What is happening to the baby?  "Nothing."  What will happen to the baby?  The baby will be named.  This is a naming ritual." Is the baby a boy or a girl?   "The baby is a boy." What will they name him?  "He will be named Breean." Go to the end of your life and tell me how you die.  "I am very old and hunting is a chore for me.  I lie down outside near my cave.  I look around, it is very beautiful, it has been a good life.  I leave my body."  What  does the body look like?  "It is laying on its left side.  It is old, but still quite beautiful."

Where are you?  "I am in my ship coming close to the enemy transport."  Are you at war?  "Yes, we saw them on our scanners, and know of their intent.  They will invade our system."  Why are you so close to them?  Are you going to attack their ship?  "Oh no!  I'm not large enough to do that.  I am a spy.  They think I'm a trader.  All I have to do is get close enough to download the information in their ship systems, which will include their number, placement and intent.  The blueprint for their attack."  Then what will you do?  Go back home?  "I wish that would be so, however I will probably be taken.  If I can get close enough without them recognizing me, I can blow this ship and they will not be able to find out much about our technology.   They still think I'm a trader, but they are quite ruthless about interrogation and they are suspicious of anyone who approaches them."
(I rock back in my chair.)  What just happened?  "They caught me, and I blasted the ship before they could do anything else."  (I'm smiling.)  Did you get their information?  Why are you smiling?  "I got everything.  They thought I had to download the information and then send it.  We have just added new technology to my spy ship that allows the information to be sent to a backup as it is being gathered.  That's what I did.  My backup has the information.  We will win now.  What is happening now?  "My ship has blown and my body is in pieces.  I am looking at my backup and he has everything he needs to stop them successfully.  He is closing in at attack speed with our fleet and they don't see him yet.  I am happy I could do this for my home planet."  Are you in any pain?  "There was no time for that, the blast blew the ship as I triggered the mechanism for it.  Just a very large bang.  I could feel their surprise, I didn't feel any pain."

Where are you?  "I'm at school."  What are you wearing?  "A white robe and sandals."  How old are you?  "Ten years old." What is this school?  "This is the Essene school near Jerusalem." Are you from here?  "No, I am from Egypt."  Why are you going here?  "My parents are Essenes and so am I." Who is your teacher?  "Mary, the mother of one of my classmates."  What is the name of your classmate whose mother is teaching you?  "Jesus"   How old is he?  " He is about 2 1/2 years younger than me."
Does his father teach at the school too?  "No, his father is a carpenter in the village." What is his name?  "Joseph".  (NOTE:  This regression is in progress and will become a book.)