Vipul Shaha — Refund cheque issue

I have purchased a Cruiser from Kate Motors Baramati.I have paid full amount in cash.The authorised person there Mr.Gaikwad had brought a cheque of 15000 to me on my name bur did not handover it to me and asked me for some purchase from me of 15000/- on the other hand when I said no he took the cheque back and took only a bill of 15000 from Gayatri Garage. I asked the onwer of the same he replied I will let you know.Why had he brought the cheque of the same as that time my 3 friends also purchased the were got a refund of the same.I think there is some fishy about that as Mr.Gaikwad says I will give u the cheque and the owner says I do not know abou that anything.Also he did not hand me the duly signed service coupons