Bad starter or bad battery/or terminals?

I got a brand new alternator because the car's voltages was under 12.5

Now when you try and turn on the car you hear click noise
Click
Click
Click
Click
Click

The mechanic got something to start banging on the starter, and then It turns on
It'll turn on really good for a few times, but then go "click click click click click click" for a while

Starter, or battery cables?
I just bought a starter because I really thought it was but some people are telling me it's the battery…

Added (1). Car is a Honda Accord 1999

It could be a bad battery, corroded battery terminals, starter solenoid, or the starter. I would service the battery terminals first. If that doesn't help I would get a voltmeter and check the voltage on the battery terminals while trying to start it. If the voltage drops below 10 volts while trying to start, the battery is bad or not fully charged. If the voltage is above 10 volts while trying to start and it just clicks I would service the starter solenoid. If the solenoid is good the starter motor is bad.

If you get tired of the problem I'll trade you my Buick for your Honda.

If you have good battery power available to the starter and grounds are good, I would agree it's the starter. Testing is always best.

? This car is a piece of junk, I will trade it in a heartbeat for your Buick
What year Is it and where do you live?