It can also become clogged if the tenants flush inappropriate material or items.

Can you elaborate more on these alternative investments ?  

The options I am considering are:  Refinance my house and pull out all the equity or draw the HELOC I have on it.The down payment would be about 20% of my total network.Which of these two would be a better alternative to get these funds?

The problem with this is the material costs can vary and you would need to determine if you would use the cost of material that is similar or exact replacements. 

Therefore, resident on first floor needs to make an effort to wake up by an alternative means (e.g. buy a vibrating device).

Also the treatments on passive loss limitations can differ to dependent on material involvement 

Alternatively you can refinance and take money out without a tax hit

When you look at a place, what sources do you use to plan colors, material types, layouts (if a floor plan needs redesigning)?

Read some material online (and we're going to higher CPA later) but seems that mortgage interest can be shown as an expense on Schedule E. 

If anyone has any sample agreements, suggestions, or materials they are willing to share, please do so here or PM me.