The seller wants a higher price than what the CMA indicates the property is worth. The seller insists on a “valuation”. What specialist advice would you recommend?

Hi Ayesha,
By the sound of this you are buying a property off-market? Typically the CMA will be conservative to between 5 and 10% under the market value as it is intended to be the price that could be achieved in a realisation sale rather than the best price the market will pay.
You should consider you're needs and goals, perhaps with the help of a financial planner and decide on the price that you are willing to pay. The seller can really ask for any price they want, it is up to the buyer to ensure they buy at an appropriate price
Best of luck
Regards
Scott