In the beginning, I didn't even know what common terms of REI were. 

If such is the case, the tenants in the lower flat will hear the tenants in the upper flat walking around, and kids running around upstairs can amp up that noise.If the flats have a common forced air furnace (or if there are two furnaces in a common basement or attic), muted conversations will make their way between the units.

In most common methods of wholesaling you are NOT a principal, you are an intermediary.8.

To my knowledge there are no HUD memos addressing this currently.More than anything, it is not common to offer rent discounts for certain professions, because most landlords want to rent their property fast to good tenants. 

The most common inquiry we get from our clients is asking for their Annual Owner Statement and/or 1099-MISC.

We NEVER markup pricing but it is a VERY common tactic.4.

A common objection I hear when speaking to sellers is that they'd love to sell to me subject to but it will affect their DTI when they go to buy a new house.

Where I live, duplexes are NOT common.

Well, fortunately they didn't listen to me, sold at a fat profit and bought a house in Boca Raton. 

Here's some clarification and advice regarding your client's concerns about purchasing a property with a CLTA (California Land Title Association) policy:Understanding CLTA PolicyCLTA Policy: A CLTA policy is a type of title insurance policy commonly used in California.