Do I have to do a geotechinical study prior to buying a land?

[Grace Wang]

Hi Everyone, 

I have a piece of land under contract, and doing feasibility studies. It is my first time, so have a lot of questions. First of all, is it a must to conduct a geotechnical study and land survey prior to close the deal? How much does those normally cost? Any recommendations for geotechnical engineer and land surveyor? 

Also if there is a shared driveway among three properties, and there is no exiting private road access agreement, is it a good idea to contact the other owners to see if they are willing to come to agreement before closing the deal? 

Your input would be very much appreciated !