We need details:
Do you want to drill the tank?
Do you want a fuge?
but in time/hassle it depends how able you are with your hands,
Being a computer nerd, I am not very good when it comes the those things and I built my sump in 5 hours total work time, not including silicone dry and cure time, and pvc cement dry and cure time.
But that doesn't include the research, I designed my own pipe style overflow, it's more of a self priming syphon to be exact, so that added some time to it.
Cost was around $120 considering I salvaged a pump I had lying around.
Hassle wasn't that much, considering I enjoyed my work.
But the time is really a relative thing, my sump is simple so it didn't take long, pipe in, pipe out, a fuge, a stand in protien skimmer, 4 baffles.