Hey buddy, welcome to Steemit. It was good to see you in Nayarit. It looks like I'm moving to Puerto Vallarta in a few months, so I'll be going through a similar process of stripping down my possessions. It's kinda stressful, but also liberating.
By the way, a little note about your English. When you say "You must not..." that's a command. e.g. "You must not feed the pigeons." - feeding the pigeons is prohibited.
In this case "You can, but you most certainly must not invest any money in Steemit to get started." I think you meant to write "You don't have to invest any money" - meaning, there is no obligation.
Good luck!
It was good seeing you as well, thanks for the help with my English. :)
That's one way to say it, but it'd be even clearer to include the main verb with the first auxiliary (or modal), namely "can", like this: "You can invest money, but you most certainly do not have to ...".
Changed it after @churdtzu commented on it. :)