We see lots of S2000s with very low miles that haven't had any maintenance.
Even with only 18,000 miles, this is 15 years old.
Here's a few things that we recommend and some tips and tricks on how to do them.
Fluid Pump
https://www.amazon.com/Performance-Tool-W1139-Gallon-Design/dp/B00329VL3G/ref=sr_1_4?crid=35I077ZF7FM44&dchild=1&keywords=performance+tool+w1141+fluid+transfer+pump&qid=1628025684&sprefix=fluid+pump+performance+%2Caps%2C189&sr=8-4
The Best Oil Filter Tool
https://www.lhtperformance.com/product-page/s2000-oil-filter-tool
The Best Oil Cap Wrench:
https://www.lhtperformance.com/product-page/lht-oil-cap-tool