There are plenty of choices and I too have a 2018 JCW HT but only the NBT 6.5" without Navigation but a backup camera. I found lots of Carplay/Android auto add on's off Aliexpress but also found Road Top Carplay/Android from Amazon. It's a bit more expensive than Aliexpress but you can't beat 2-day Prime delivery. Installed yesterday and now tinkering with it to add a separate CarlinKit unit to watch different apps.
Installation was very straight forward but like any or all electronics, instructions were very limited but enough to get by.....
Road Top Wireless Carplay Retrofit Kit Decoder for BMW Mini Cooper
Installation was very straight forward but like any or all electronics, instructions were very limited but enough to get by.....
Road Top Wireless Carplay Retrofit Kit Decoder for BMW Mini Cooper

Amazon.com: Road Top Wireless Carplay Retrofit Kit Decoder for BMW Mini Cooper One Hatch Clubman F55 F56 F54 F57 NBT System 2014-2018 Year, Support Android Auto, Mirrorlink, Reverse Camera : Electronics
Amazon.com: Road Top Wireless Carplay Retrofit Kit Decoder for BMW Mini Cooper One Hatch Clubman F55 F56 F54 F57 NBT System 2014-2018 Year, Support Android Auto, Mirrorlink, Reverse Camera : Electronics
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