what is the best thing to invest in. i was thinking weapons 1st then armor then assecories then food? any advice on what lvls i should keep them at, splurge on one or try to keep them even or what?

I'd keep them relatively even, though I personally prioritized on Accessories. Don't level up food too much, and I'd probably level armor over weapons. Really, you can't mess it up too much unless you just level Food and nothing else :P

In my experience Items/food are the one you need the less For the rest always and only upgrade while you are getting a bonus do not waste your stuff. But yeah if you have to chose between Weapons or Armor I would go with Weapons and then armor. But if only one gives a bonus use that instead.

When you go into the upgrade screen pay attention to thr symbol by thr shop. That means if you trade items of that type you get double sometimes even triple the points of that item. Only ever use items that you get bonuses on. Also, you'll get plenty of upgrade materials over the course of thr game. Don't be afraid to pump your resources into upgrades every time you reach a new town. As for what to upgrade that is up to you.

aw thx a lot for the help. i didnt even pay attention to the symbols, getting a x3 help a bunch!

I put everything on a 50/50 split (only leaving one of each item for quests) on what has x3.