This area; around here — referring to the nearby place or vicinity.
この辺に美味しいレストランがありますか？
Is there a good restaurant around here?
この辺は夜になると静かになる。
This area gets quiet at night.
駅はこの辺のはずだけど、少し道を間違えたかもしれない。
The station should be around here, but I might have taken a wrong turn.
This point/extent; this much — indicating an approximate degree or limit (e.g., "let's stop around here").
もうこの辺でやめておいたほうがいいよ。
You'd better stop around here.
値段はこの辺が妥当だと思う。
I think this price range is reasonable.