Most marinas require insurance before they will rent you a slip. The other requirements very a bit with everything from a picture of the boat to registration to a credit check. The harbor master may not like your looks or have a history with the boat you just bought and just want it out of the marina. Apparently a common scam people use when they get kicked out of a marina is to claim they sold the boat. After a few rounds of this, Harbor masters won't listen to reason, they just want 'that' boat out. On any boat over 20 years old the insurance company will require a marine survey be done before they will insure the boat. There are two types of marine survey, in the water and haul out. Marine surveys run $10-$12 per foot and haul out is another ~$10 per foot. It can add another $600 to the purchase price of a 24' boat and take more then a few weeks to get everything scheduled. Contact the insurance company to find out which type of haul out they require. You may notice there is a cart-horse thing here: If the boat isn't located where a marine survey can be done, you may have trouble moving it some place where it can be done w/o insurance. There are professional boat movers but their fees are not cheap. I used an insurance company that accepted an in water survey because of this. The good news about a marine survey is they can be good for two years. Insurance will also require any critical issues be taken care of before they will issue a policy. Once again, if the harbor master wants the boat out NOW, you may not be given time to fix things. Clear title is a definite plus for any boat. Once again it is a requirement for both insurance and renting a slip. If there are any outstanding liens against the boat it could cloud title for weeks while you clear them. A tipoff of title problems is if the boat isn't currently registered.