1997 Chevy Cavalier Ticking noise in engine

My daughter's car is making a ticking sound under the hood. My friend looked at the car and thought it was a rocker arm initially, but after tightening things up and doing a few things, he now thinks she needs a new engine. Any other things it could be before we shell out a bunch of money to fix this? It's cheaper to fix it than to buy another car at this point, we believe. My husband is a suspension tech for Chevy and get parts for family at cost.