and "what constitutes as a buyer?

Income earned in an active manner is subject to self employment tax, I did.As to voting rights, depends on state law, but I had LLCs where members had different classifications and voting rights, that in and of itself does not constitute a securities issue, all rights do not have to be equal.

IE.The note will recite the lender and borrower, the property, and the debt created to be;A Principal Part of the First Part (PPFP) in the original amount of 100,000 bearing interest at blah blah....Together with A Principal Part of the Second Part (PPSP) in the original amount of 25,000 bearing interest at the rate of ....With such principal amounts constituting the Total Principal Amount of 125,000, hereby created and secured by that deed of trust made of even date.....This sets aside the PPFP for example to be assigned for a number of circumstances or the entire loan can be viewed as one note.This is handy for investors as you may recite in the LLC capital account that the PPFP shall be credited to John and the PPSP assigned to Fred....It's great too for estate planning where one beneficiary may get the PPFP and another gets the PPSP.You can have as many parts as necessary, I had eight in one loan for a trust.

Let's hope there are many more to come.I highly recommend you learn what constitutes a good investment.

What constitute doing business varies state by state.  

Landlord’s requests and notices to any one Tenant(s) constitute notice to all Tenant(s) and occupants.

California Code, Business and Professions Code (BPC) 10131 addresses this, and states that the following activities constitute the practice of real estate and thus require a real estate license:A real estate broker within the meaning of this part is a person who, for a compensation or in expectation of a compensation, regardless of the form or time of payment, does or negotiates to do one or more of the following acts for another or others:(b) Leases or rents or offers to lease or rent, or places for rent, or solicits listings of places for rent, or solicits for prospective tenants, or negotiates the sale, purchase, or exchanges of leases on real property, or on a business opportunity, or collects rents from real property, or improvements thereon, or from business opportunities.

This is part of the reason Alabama needs to get rid of its ancient and way too long constitution and redo it right.

Would that then constitute an STR because they stayed with you and you recieved payment in one form or another?

For the complete and up-to-date constitution and statutes, check the Texas gov website.What is a statute of limitation (SOL)?