Hello I am a solicitor with over 15 years experience. I will try to answer your question.
I assume he is not alleging any fault with the instrument.
It sounds like you have a contract and he is now breaching the contract. How short are you on the deal?
no I have spoken to him and he was happy with the instrument , he was supposed to send the instrument last Thursday and kept making excuses for not sending it , he suggested that would I be willing for him to make up the difference with cash and I said this would not be a problem but he avoiding me .
I did happen to post a message on his face book page , that got his attention
You should give him a warning that you expect the balance paid, set out the terms of your agreement give him a time limit to make the payment. You can threaten him with a claim in the small claims court if he doesn't honour his obligations within the time limit (usually between 14-28 days).
Follow this link http://www.adviceguide.org.uk/wales/law_w/law_legal_system_e/law_taking_legal_action_e/small_claims.htm to the CAB information page on bringing a small money claim. It is very helpful.
Did not get a chance to respond
Does the instrument remain my property because it has not been paid for in full
That depends. You could demand return of the instrument but then you would need to return the money minus your costs incurred as a result of his breach. You should probably give him a chance to make good on his promises before treating the contract as void (which is what a demand for return of your property would amount to) due to a fundamental breach by the buyer.
How much has he paid so far?
The small claims court can only deal with money claims. It could not order return of the property. The value of this claim would make using any other court track impractical so in practical terms your only remedy lies in the small claims court.
Thank you I ve text him out lining that he has till Friday to pay the moneys into my account, if this does not happen then I will take action via the courts , I would prefer to pay him back the money that he has paid and reclaim the instrument.The original deal was £1699 he paid £1450 and the rest to be made up on the px , I agreed that a cash payment of £175.00 in place of the px , also giving discount