For instance, depending on your location insurance costs could be much much higher than indicated in the book, construction costs are a lot higher, etc. 

The longer the maturity rate of the bond, the higher the yield is to compensate an investor for the additional risk they are taking on with a longer dated bond.Stocks that pay divideneds....insurance companies have a lower yield than telecom stocks as a reflection that telecoms are higher risk than insurance companies.In the efficient market hypothesis, if markets are efficient then the yields should be reflective of the risk.

what is damage protection insurance? 

You will truly be raising the clock, as each day will cost you very significant money.  12% interest on $250k is $2500/mo, or about $80 per day in interest, not including your other carrying costs (utilities, property taxes, insurance, HOA). 

For the person that is letting you arbitrage their property, why would they choose to let you arbitrage their property rather than hire a professional, licensed, insured PM that has a team to run their property for them? 

In addition, 1031 Exchange Qualified Intermediaries are generally not required to be bonded, insured or maintain any other form of minimum equity capitalization.

Deduct NEW property taxes after you buyDeduct home insurance costsDeduct maintenance percentage, typically 10%Deduct vacancy+tenant nonperformance percentage(we recommend 5% for Class A, 10% Class B, 20% Class C, good luck with Class D)Deduct whatever dollar/percentage of cashflow you wantNow, what you have left over is the amount for debt service.Enter it into a mortgage calculator, with current interest rate for an investment property, to determine your maximum mortgage amount.Divide the mortgage amount by either 75% or 80%, depending on the required down payment percentage - this is your tentative price to offer.If the property needs repairs, you'll want to deduct 110%-120% of the estimated repairs from this amount.Be sure to also research the ARV and make sure it's 10-20% higher than your tentative purchase price.As long as the ARV checks out, this is the purchase price to offer.It is probably significantly below the asking price.

Expenses: What are the operating expenses, including taxes, insurance, maintenance, and reserves?

Here it would be 25% down ($275k)A balance of $825k at 7% (or higher) $5,490/mo, figure $250/mo insurance, $500/mo property taxes $6,250/mo. 

1) As an agent put 3 more under contract this month for going into 20252) Cut internet and car insurance bill down3) Start prepping for tax time, organize expenses yay lol