There are some really good used boat buying guides out there, but one thing I've found they seem to overlook is transom rot or damage. So here is an additional tip.

There some really good looking boats for sale that seem to be in good shape, but with a weak transom. When doing your check of the boat, lock the motor in the tilted position and take hold of the lower unit and put pressure up and down while looking for transom movement. On a good solid boat there should be very little, or none at all.

Look for cracks/splits to either side of the motor. If there are the motor has probably hit something very hard.

Keep in mind that transom repair is very expensive ( usually in excess of 2000 dollars if done by a repair shop). If you are a competent do it yourselfer it still runs close to 1000 dollars in materials and a lot of time and work on your part.

These boats can still be worth buying in some cases. If the boat is worth the purchase price plus the added expense of the repair and in good condition over all, this may be a good deal for you. After repair/rebuild ( if done right) you should have many years of service from the boat.

Also after purchasing any boat consider purchasing a transom saver ( specially in the case of higher horsepower motors). This device lets the weight of the motor rest against the trailer when trailering thereby decreasing the risk of transom damage due to motor bounce on rough road conditions. These devices can be found for less than 50 dollars and compared to the price of transom repair are a very wise investment.

I hope you have found this tip helpful. Happy boating!!!!