ok im sellin the scarab im going to look at a 1978 24 in what looks like good shape. merc 454 with a trs drive what should i look for? are these boats like the old cig's where the age is not really a factor too much?

With a 30+ year old boat it is hard to tell, but any boat that old can have wetness. Check for stresscracks, and get a survey.

I owned a 28' Cig and a 24' Superboat. The construction of the two boats is like comparing apples to oranges.
Like the previous poster said, any old boat needs to be looked at closely...

How would you compare the construction of your velocity to the 28 cig or superboat?

Somewhere in between...

I would check the hull for soft spots. I use a small wooden hammer like the one you for cracking shells at dinner. Go around with that and listen. You can hear the difference between hard/solid/good and soft/spongie/bad. Very easy to do. Still plenty of trs parts around but converting the boat to a bravo will help the boat lots.