Scammer posing as an agent for bnbs and houses in Kiambu

Yesterday I had my own experience. They said they had some bedsitters in kiambu town. I reached out to them and told them I want to come and view. They told me to reach kiambu mall and call them. I called them and they said that I should first send 500 to get a receipt and then they will give me the caretakers number. I told them I had cash I can give them once we have viewed the house. He insisted that I send the money first. I sent because I was desperate to move urgently and I really wanted to get the house. After sending the money he sent me the caretakers number and I called him and he said he doesn't know anyone by that name and that the guy has been using his number to scam many people. After I tried to call to get a refund he blocked my number