Solar power pack

I have seen some threads about this but haven't found the answer I'm looking for.

I have an old car battery, out of a Jeep. It has roughly 800-900 CCA, I don't remember right offhand. I was wondering if I could use this for a power pack I could use for yard work. I realize it might not be the most ideal battery but it's what I have for the moment.

Can I use it?

"old" - likely have little to no capacity remaining.
"car battery" = extremely short cycle life and incapable of deep discharges without sustaining damage.

"can" = ability. Yes. You can use it.

Should you? No.

If you want to build a system and use it for "prototyping" purposes before you invest in a good battery, then go for it.

Ok that being said, let's go with "can," and it really is until I can get a better battery.

What size inverter? I'm thinking 2000W since the highest amp rating I'll be working with is 15 amps. Also thinking 100W solar panel.

15A to power what?

Chainsaw, maybe a table saw

Non-trivial demands.

Electric motors have a large surge current that uses 3-10X the run current. You will need a powerful inverter for this, and a weak 12V battery may not be able to supply enough current and maintain minimum voltage thus shutting down the inverter.

The best way to design a system is to define what you are designing for - in detail, i.e., "I want to run these A devices that use B Watts for C hours per day."