Bmw chris

Hi I wonder if the community could advise please in the valuation for my Z4. Looking in the auto trader the prices are changing daily. I have a 2012 z4 2.0 m sport sdrive, full bmw history for all work and only 45k. I have cherished this car and only used it in the summer and the condition reflects that. can anyone advise where I would need to be on price as it’s not just another z4 on autotrader and I’m not un a hurry to sell it ? hope you can help