There is no secret that art supplies are expensive. If you come across cost cutting methods or techniques that work then you have to use it.
As I paint in oils I clean my brushes using Turpentine. I use general household turps that you buy from the hardware store for the task.
To clean the brushes do this:
First wipe off all the excess paint on a rag and then swirl the brush around in a container with turps. Wipe the brush again on a rag and repeat the process. Use dishwashing soap to wash the brush. As I stay in South Africa we use Sunlight liquid soap. Drop a little bit of soap in the palm of my hand. Wet the brush and swirl the brush around in your palm until it make a foamy lather. Then rinse the brush in clean water. Keep repeating the soap in hand palm motion until the brush comes out completely clean. Finally lay the brush flat to dry.
To recycle the turps do this:
Use two glass bottles for this. In this case I just used some old Mayonnaise bottles. In the one bottle drain the turps that was used to clean the brushes with. Once all the gunk has settled at the bottom of the bottle carefully pour the clean liquid in the other glass bottle. Making sure that you do not get any gunk in the ‘clean’ turps bottle. The turps do eventually look yellowish almost like urine but has no influence on the brushes or artwork as you clean them between uses. When you start a new painting pour some of the ‘clean’ turps into the container you used to clean the brushes with. If you don’t have enough clean turps in the brush wash container then add clean turps straight from the store bought bottle.
Very important: Never use household turps as a thinning medium in your paint. It will flake off in time and ruin the painting. That would also be very embarrassing if a client were to call you up and their artwork is ruined.
Even though I do have a nice brush holder you can simply cut open a tuna can and use that as your turps holder. I used this for years before I bought a brush holder. It does not rust and lasts forever. To clean the container simply pour out the turps in your recycling bottles as above and give it a good wash with dishwashing soap and wipe out and dry with a paper towel. Do not leave old dirty turps in it too long as the paint gunk later gets very hard and gets stuck to the bottom and it is then hard to remove.
Hope these tips can be of some help to you.