How I was almost duped by fraudsters

Lmao I was almost duped today. I went to get a phone at Robinson Plaza for a friend. Having had lots of experiences with these dudes who accost you on the way and escort you to the store only to end up extorting lots of money from you in the name of installation, I was prepared for them. When they came towards me, I simply ignored them. One asked if I wanted to buy a phone or any other gadget, saying he knew the right store to take me to. Another said I shouldn't think he's trying to dupe me or anything, he said he's only offering to help so I wouldn't be cheated…yeah right.
Anyways, after a little search, I finally decided on the phone I wanted. While I was paying the seller, one of the guys who followed me to the store said when I'm done I should come with him so he'd help me do the warranty. Wow, I thought to myself, that's a new one. Usually the words they use were, I'll help you configure it, or I'll install some apps for you so you could enjoy your phone very well. This warranty was a new one and I simply smiled. As I handed the money over to the sales girl, she pinched my handed a little which was a warning not to go with the guy. I smiled my thanks and got out of the store. Outside, the guy said come on lemme take you to my store and lets do the warranty for you. My curiosity got the better part of me and I followed him.
At his store, he gave the new phone to his friend and they gave me a chair to sit. I quickly asked how much he's going to charge me. He tried avoiding the question by saying there was no fixed price. I insisted on him telling me the amount until he finally said 400-800 naira only.
I gave him back the phone and he connected it to his laptop. Copied my imei number and showed me a message that read…warranty successfully installed. He gave me back my phone and told me my money was 2500. I burst into laughter and told him what about the 400 naira he told me. He said how could he do that kind of job for a mere 400 naira, and asked if I knew how much they've just deducted from his account? Smiling I said how much. He hissed and said if I didn't want to pay I could go. Smiling I said okay, picked up my bag and started leaving. His friend chased me down and said I shouldn't leave. That if I did, he had the serial number of my phone and could do anything to it that would make the phone useless and I'd eventually come back to beg him. I looked at them and wondered if these guys actually thought I was that stupid…I walked back to the store and the other guy was like "who called you back? You would have left now and I would have seen how you would have used your phone' smiling, I brought out a thousand naira, gave it to him. He looked at me angrily and asked if I thought he was a beggar that I was giving him just 1k. and that's when my "serious face" face came on and I told him he couldn't do jack to my phone cos as soon as I walked out of here I was going to change the imei number as soon as I got a simcard and hence what he had would be useless. Shocked at what I said he tried covering up by saying I don't know what I'm talking about and if I wasn't scared I should go and then I would see what would happen to my phone next. I smiled again, walked to the next store, bought a glo simcard and changed the imei of my phone under three minutes while they all gaped at me…then I walked back to them removed my sunglasses, looked into each of their eyes and said, if you try anything funny to this phone, it would be the last time you'd step into this plaza alive, I've got your life serial number with me. I put my sunglasses back on like a boss and walked out of the store confidently praying deep within that none of the mean looking guys would try to stop me