What problems may occur here ?

I am looking at buying a 16m Randell which is currently being used as a tug in Rarotonga pushing the container ships into the wharf. What or where would there be any stress on the hull that I should be looking out for ?

 

Everywhere!

Crushing, girding, sinking, fire, any signs of these are not good.

 

If there are any marine surveyors in the area you trust, use them. Or BYO.

 

When buying a boat, look for a third party surveyor and ask for a "Condition Survey". The surveyor asses the general condition of the structure, machineries, FIFI, equipments, Navcom, ect. You do the math on how much money you will have to fork out to put the boat in serviceable condition.

A more expensive survey is "Valuation Survey" wherein the general condition of the boat value is compared with existing ones in the locality and repairs/retrofit is estimated to give you a ball park figure on how much the overall cost will be. This is done by more experienced surveyors.