how much do i need to start this hobby? sounds fun and a lot of patience and learning needed.

Yea 500 should be enough.

But it might go higher on lower depending on what items your getting as I have calculated my budget.

If your on a tight budget you will have to use these items:
Basic aquarium normal non clear glass.
Some cheaper shrimps.
Use sand for substrate instead of shrimp soil or ADA soil.
Cheaper plants that they normally sell in LFS.
PVC Pipe as a ceramic house replacement.

If like this I think will cost you around 200 to 300 only.

Good luck.