Help I need some boating wisdom

I am looking to buy a used boat I can fish from and I can take family and
friends on. So far we like the deck boat option. I want to buy an older
boat, but need information to determine how old and what make and model boat
I am comfortable with. I am used to using Consumer Reports to investigate a
car purchase, but I have not found similar information on boats and boat
engines. Can anyone tell me the best place to find this info?

I have found two boats I am wondering about. a 1986 20 foot hurricane deck
boat with a 175 horse Evenrude and a 1993 20 foot hurricane deck boat with a
150 horse Evenrude.

I have heard that I should avoid Evenrude because of quality and parts
availability. I have also heard that Evenrude engines are fine and that I
will not have a problem finding someone to work on it.

Which is true???

I have heard that if a boat engine is well taken care of that they last
forever so buying an older engine makes some sense. I have also heard that
many places will not work on old engines and that I would be sorry.

Please share your wisdom.