Instend of building a sub why not buy and existing one that has been decomissioned?
Submarines for sale:
Name: Project 877 or 636 class (NATO: Kilo class)
Country of Origin: Russia
Pros: Highly capable boat. Highly automated.
Cons: High cost. Large size.
Cost: 300 Million USD
Name: Project 865 class (NATO: Losos class)
Country of Origin: Russia (Via Russian Mob! No BS!!)
Pros: Recent design.
Cons: Poorly maintained for the past 2 decades.
Cost: ???
Name: Project 613 class (NATO: Whiskey class)
Country of Origin: Russia Via Ebay
Pros: Actually for sale to private owners.
Cons: Operational condition questionable. Probable death trap. Few spares.
Cost: ???
Name: GUPPY class (Hai Pao, Hai Sha)
Country of Origin: United States via Taiwan or others
Pros: Well known systems. Many former crew members in US
Cons: Very old. Few spares. Operational condition questionable. Probable death trap.
Cost: ???
Name: Agosta class
Country of Origin: France
Pros: Not very old. Of western design.
Cons: high cost.
Cost: 250 Million USD
Name: Daphne class
Country of Origin: France (Pakistan, Portugal, Spain and South Africa also may sell units)
Pros: Small size = low operating costs.
Cons: Old design with questionable safety record
Cost: ???
Name: Sava class
Country of Origin: Former Yugoslavia
Pros:
Cons: Operational condition questionable. Few spare parts available.
Cost: ???
Name: Una (Velbit) class Midget Submarine
Country of Origin: Former Yugoslavia (Croatia and Slovenia have units for sale) visit
www.aalan.hr
Pros:
Cons: Electric propulsion only except in Velebit which has a diesel engine.
Cost: ???
Name: Oberon Class
Country of Origin: UK
Pros: Recently retired from 2nd owners. Plenty of former crew members available in UK, Canada and Aus.
Cons: Hulls are old. Spares a problem.
Cost: ???