Some property managers will also give discounts depending on the number of doors.

It really depends on location, quality of home features, amount of privacy for renters/members, and competition.

I think it all depends on what you are looking to do with the social media / how you want it to help you.

The income (rent minus management) should cover the costs (principle, interest, taxes, and insurance) depending on the property's price point. 

It really depends on the lender.

They have every incentive to make sure construction is up to standard since they will receive 5-6% (to be split with buyer's agent depending on state) of the sale price in commission.

Now, some of these answers will depend on what state that property is in, how much equity you have, and a couple of other factors...but you can certainly seek out other lenders about a Line of Credit on an investment property.  

Because of all of this depending on your investment goals, one may make more sense than the other. 

It depends upon what your current rate is, how much equity you have in the property, does your current financing have a prepay, and what your plan is for deploying any cash out.

Discount depends on model but the discount is about 50% off of retail,  and arrives within a week direct from manufacturer.