Is it a good deal?

2019 honda wr-v diesel vx model (first owner) with 65k on odo with full service record. Test drove the car and to me, it’s in a really good condition with minor scratches and dents. Asking price by the dealer is 7L which I negotiated to 6.5L. My major concerns are - one key is missing and dealer has asked the owner to find it or dealer will get me a new key. - never owned the diesel so idk the maintenance - how’s the honda’s long term review about this engine - any other thing i should be careful about