should i buy the sims 3?

No one can really tell you if it's worth it since only you'll actually know if it was worth it once you try. For me ts3 has it pros. Being able to control multiple sims at once and have them all spread out across the world is very nice and allows you to get more done. Con the world feels dead as in not enough ppl at least in areas you may like. Parks and gyms seem to always have sims but bars, clubs, beaches, and some others usually only have a handful sima so they end up feeling dead. Personally for me ts3 sims themselves only look good if you use cc to make them look realistic othetwise they usually look like pudding. One thing I now hate about ts3 is how difficult it was to edit the sims themselves. In ts4 you can go to manage households and edit them easily and can manipulate most of their features but in ts3 i believe you had to go one by one and you needed to cheat if you wanted to edit their face and body.

Overall I would just wait for a sale but if you can't the starter set isn't that much like mentioned before. Also if you end up buying EPs go one by one. Don't want to overwhelm yourself with content and not know where to start. That's what happened with me. I ended up buying several packs at the start and ended up not knowing where to start that I felt lost.