I am currently studying how to use 〜込み but it's been really hard to find any resources. So far I have made some notes based on my observation of how 〜込み is usually used, but I am not really sure if I am right. I'm hoping that someone here could have a look at my notes and let me know if I'm on the right track or I've made a mistake. ありがとうございます！
'If we use 込み in a sentence, we are usually asking if the price of using/buying a product/service is included in the price of something else.
e.g. テレビこみですか。Is the price of buying/using the TV included in the fee.
If there's anything that you would like to add please let me know as well, thank you in advance!