Like objectively bad compared to people in other professions.

Remember, no system is perfect, so avoid the temptation of constantly chasing after the next shiny object.

If you have massive liquidity then you might overcome that objection with the lender. 

Quote from @Miguel Del Mazo: Thank you for the discussion @Corby Goade .I feel like we are biting off big pieces of a complex topic, and I think it would be helpful to focus on either the interests of the property owner or the MTR operator to simplify things,I think your greater objection to MTR arbitrage lies with why a property owner would want to willlingly enter into the agreement, so I will focus my reply on that. 

Your objective- Learn, learn, learn.   

The guy even makes calls to difficult seller's live right infront of you so you can hear what an expert does to overcome objectives..

I think knowing more numbers, heloc limit, plans and objectives for future goals all should play into "what is best".

My objective is to establish my network in the region prior to my arrival.

Once you read the explanation below, you will understand how REALLY bad things can be if you don't get the letters but go through with the purchase.First, the owner/seller should have a clause in the lease requiring tenants to sign (or object to in writing) tenant estoppel letters if presented to them.

With the increased competition, it’s also crucial to prepare your listing to stand out and work to address buyer objections prior to going on market.