Is it expensive to fix the motor mounts on a 1990 Honda Civic sedan?

Is it expensive to fix the motor mounts on a 1990 Honda Civic sedan?

Depends on who does the work; a DIY only pays for the parts, a garage will cost a lot more

If you do it yourself it will probably take 4 or 5 hours. An experienced mechanic with a lift can do it in 2.