Am I missing something? 
£18k less £14k is £4k, plus a couple of services. No idea if that's an okay deal, but it's more than the figure quoted in the original post. 
 
Presumably the difference is for those aforementioned MOTs + services, which to me sounds rather steep: 
£17,998 - (£14,000 + £2,741) = £1,484 
I would've thought that each service would cost around £350, maybe £400 (it's not as though its a BMW), plus £55 (legal max) for each MOT. 
Total somewhere around £860 - £910.  What's the other £500+ going on? 
                            
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