Here are some of my hobbies that are low cost. Maybe they'll give you some ideas on things to pursue.
1. Drawing is an extremely cheap hobby as well as pastels and watercolors--other forms of painting get expensive really quick.
2. Musical instruments. Most rock band insturments like guitar, bass, keys can be bought for $100-$200 US & still be decent for a beginner. Used drums can be cheap. Lots of free video lessons online too.
3. Animation - Blender 3D is free animation program.
4. Fishing. Rods and reels under $30 at sports stores.
5. Learning languages + books.
I see you've already got that covered.