Yes. You have to invest in Steemit to make a living from it.
No. You do not have to invest any MONEY from sources other than Steemit to make a living from it.
Now that you're confused ...
You MUST invest time, effort, and emotional energy into Steemit to make a living from it. You should also invest a bit more of your earned SBD into Steemit for your first few hundred posts into STEEM and power them up!
Powering up gives you better rankings for two reasons:
- You have a more powerful upvote
- Your powerful upvote attracts the attention of others with powerful upvotes as well as the attention of hundreds more minnows and dolphins.
Investing external money is a shortcut
If you can't be patient and build a quality following, buying up your Steem Power could give you a leg up. As the community grows however, buying your way to the top could be seen as exactly that "BUYING YOUR WAY TO THE TOP" and there is a certain stigma attached to people who use such tactics.