And because of that I say that you should use a professional any time that you want to address mold correctly, using the latest standards, engineering controls (to prevent cross-contamination), trained staff, be covered by THEIR insurance, etc.I realize that many people here on BP have chosen to do it themselves and some of them don't ever have downstream problems. 

The waiver prevents any suppliers that my subs hire from putting a lien on my property if the sub doesn't pay them. 

@George Wines, I'll chime in here, but @Mike Wood and NA Beard are right on.As a former city planner in the Front Range, I can think of several legal issues preventing you from condominiumizing a duplex.  

I have found that even $50 can prevent people from looking.

Make sure you have the tenant file with you & you have documented everything (late payments, damages thus far)Everyone has the right to appeal, not sure if there is anything you can do to prevent the tenant appealing.

Make sure the note has a an agreeable extension option to prevent putting yourself in a bad position if things take longer than anticipated.

I'm guessing that part of it is due to the Régie du logement preventing rents from going up too much. 

Filing a notice of an option is an encumbrance, it's a lien that clouds title, it doesn't prevent a future sale, just as a property can be sold subject to that lien, a sewer bill, tax bill, mortgage, workman's lien or whatever, the buyer takes title subject to the lien interests held by that lien holder.

So I'm always at a loss for what to do with stairs.I normally use the metal stair edging for stairs that aren't showy: Leading to basements, etc because I feel that is best for slip/trip prevention, but I really like the look of stained (or painted dark brown) Treads with white risers, especially when there is no other carpet in house.Wooden stairs are less slip resistant compared to carpet or metal edging: fine for my house, but I worry more about slips/trips at a rental.Does anybody have any decent looking solutions?  

The LLC protection may prevent you from losing it.