Depends on the functionality you want. There are some BHW users who have released free bots with some functionality, I forget who but you should be able to search the forum easily for them.
Then your other option is to setup some github projects. There was a big post explaining how to do it with python. Again a search should find it.
But if you want something simple, effective and free, you might be out of luck hitting all three. But for sure you can find something that hits 1 (maybe 2) of thos requirements