If so, can you talk to the tenant about the issue--it's dangerous, someone could get hurt, and your insurance won't cover it.  

There is not a very strong distinction.

Dangers if I bought the house and just removed the popcorn ceiling myself?

Search here for blogs and posts related to that topic, purchase books about that investing type and begin to further narrow your niche.  4) Once you know enough to be dangerous, start engaging in BP forums.  

I will not put them in danger.

If you hire people for a dangerous job in an environment that you know is not safe, and they get hurt, then your insurance may abandon you when the injured makes a claim.

We are reading and studying about buying properties saddled with tax liens... as this sounds promising, I'm sure there are hidden risks.  Any advice or experiences are welcome.  Thank you.

We aren't talking about a dangerous narcotic.

This is a dangerous assumption and if you think repairing a mid-quality rental property is expensive, just wait until a tenant damages your property that you dumped a fortune into to get the best finishes to attract the "high quality" tenants.Tim

This being said, determining what partnership looks like to you is entirely up to you.I advise, in the beginning, have a distinct role each person plays.