This is a list of all ship models that can be found in Mass Effect: Andromeda. They are displayed above the desk in Pathfinder's quarters on the Tempest.
Missable models!
Initiative Fighter Model - Spender's Apartment on Nexus, you can pick it up while visiting this room during Nakmor Drack: Krogan Betrayal mission. If model is not collected before leaving the apartment, it'll no longer be retrievable.
Mission rewards
Tempest Model - you will receive it at the end of Movie Night: The Final Piece mission.
Some models you can buy in stores / from merchants
N01 Nomad Model - General Merchant, Nexus / Hyperion
Nexus Model - General Merchant, Nexus / Hyperion
Archon's Flagship Model - General Merchant, Nexus / Hyperion (after you complete Hunting the Archon)
Citadel Model - General Merchant, Nexus / Hyperion (after you complete The Journey to Meridian)
Kett Shuttle Model - Thrasia, Kadara
Remnant Fighter Model - Generel Goods Merchant, Aya
More
Remnant Derelict Model - On the table in Alec's HQ during or after completing Epilogue: Home and Away mission.
