In or out of the water when selling

I would advise whatever is most convenient for yourself, as any serious buyer should not be put off whether the boat is out or in. If the boats IN then advantage is you get a feel of stability, engines can be started. If the boats OUT advantage is you can inspect the hull and underwater fittings more thoroughly. Main advise is to have the boat in it's best condition and priced accordingly to the competition.
 
Top