Accept Bitcoin as payment for products or services is another way to get bitcoin by buying, only in a different way. This method is called bartering or mutual benefit. After a transaction occurs, you will be able to resell Bitcoin to replenish items that have sold out.
There are other ways that are more profitable than what you described above, you don't need to buy Bitcoin to get Bitcoin or you don't need to open a service to receive Bitcoin from your customers. Start contributing to the forum to reach Full Member rank, you can apply for one of the paid BTC signature campaigns, if the manager accepts you, then you will get Bitcoin without having to buy.