If you are looking at obtaining a higher valuation, they could change the valuation if there was a legitimate reason for doing so i.e. improvements on the property. However if this is for settlement reasons, you can look at instructing different agents to value the property and use the ones that suit you. However the other side will do the same for a lower amount and you will want to establish fair market value.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
https://www.lawsoc-ni.org/solicitors (N. Ireland)
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