Assim Al Hakeem

Kindly refer to the following link(s):

Should we say Ameen after reciting Fatiha in Duhr and Asr & sunnah prayers as well? And if I pray the ‘loud’ prayer alone, should I say Ameen out loud? | Sheikh Assim Al Hakeem (website)

Is it from the Sunnah to say Ameen loudly after Fatiha? 

Should Ameen be said loudly or silently after fatiha? 

When to say Ameen after Fateha, before the Imam says it or with the Imam or after?