End of September would be an acceptable time for me to move. What country would the shipyard be ?
Is the submarine intended for military use or as a civilian ship for submarine yacht use, salvatage, etc...?
The specifications you mention do not seem to be very ambicious - 500 nautical miles is little range even compared with WW2 diesel subs i asume this depends more on your engine and its specifics than on the sub.
A dive depth of 250 feet is easily achiveable.
The speed is basicly given by length / diameter ratio from displacement hull formula as for any submarine. As a rough calculation put the speed of a similar sized heavy surface ship and add a little extra for lack of wave resistance this is what you will get from a clean streamlined submarine hull.
For basic calculation i would suggest you take some 50% of the displacement for hull weight and still have some 50% of the displacement for AIP Engine, fuel, machinery, load and ballast.
What kind of AIP Engine we are talking about ? Sterling, Walter, Fuel Cell, Diesel recycle...
Does the engine require that we build the boat around it or design it seperable in sections, or can we build in the engine - after hull is terminated - trough the hatch or a provisorial opening.
What would the boat be marketed for ?
The cost of the hull depends widly on how many viewports are needed - if any -, what grade of complexity the forming is going to be. The needs of concrete testing, guarantee, clasification which comes with extra cost. If those factors are in general fafourable - as it should be in concept testing you can calculate crude hull construction cost at a base of 331 Euro/ton of displacement.
Viewports, machinery, shipyard rental all this are calculations apart i can not give you the numbers for at this point.
What concerns my remuneration - make an offer. My conditions are basicly: i want to live near the shipyard in acceptable conditions, bring my wife with me and have the posibility to visit my kids living in colombia during vacations.
What time frame you are planning for this project ? What would my position be ? How many workers, engineering team ? Is Budget solid ?
Let me hear your thoughts...