Before I give you the invoice for the work I have some paprework for you to complete, you have in front of you data on your cars engines performance, work out probability of what we have done to the EMS and confirm the predicted outcomes from the two given variables showing any correlation, determine how much you think is going to cost. Here is a clip board for you to write on, and if you could just take a seat, please show you working out and no talking to the person next to you or looking what they have written. When finished I’ll check your working out before giving you the proper answer and our bill.
An estimate? Tell you what: why don't I just go ahead and do the work, and you can pay me what you think is fair when I'm done? You can use my Jag while I'm fixing your Renault 2CV.