Salem has undergone steady growth for the last 15 or 20 years and I attribute much of that to the state government and resultant high paying jobs.  

Currently I maintain an Excel spreadsheet with 3 worksheets, 2 for my rental properties and 1 for general LLC expenses not attributable to any particular property.

From the wording of your question, I get the sense that you either got or are expecting a credit on the HUD-1 for the property taxes attributed to the seller's period of ownership.

A simple accounting system will have property accounts, income and expenses and a general ledger for espenses that are not attributed to a particular property, as well as other income like interest income and accounts for your escrows.

The improved value on the date of purchase is not a % of the purchase amount, it's the actual dollar amount at purchase that is attributed to improved(non land) value.Also remember tax value only deals with what local municipalities say your property is worth, the IRS isn't really concerned with that.

If you provide the data to the appraiser showing that the property in question has attributes comparable to let's say properties in $120K rage, versus $100K range, the appraiser will take this data in consideration. 

If you're interested in renting to college kids springfield is a fine option there weren't nearly as many destructive parties down there as I see in warrensburg on the weekends I attribute it to the agriculture focus of the school farm kids tend to work on the weekends.

The real estate asset is not a qualified property for 100% bonus depreciation or section 179 election.Yes when you 1031 exchange, you tax attributes carries forward.  

In addition, if you are self-employed with no full-time employees you may wish to consider opening a Solo 401k instead of a self-directed IRA as it has several advantages over an IRA LLC such as much higher contribution limits, direct checkbook control (i.e. no need to have the account at a specialty trust company), ability to take a 401k loan, exclusion from unrelated debt finance income tax with respect to investment in real estate acquired with non-recourse financing, etc.In addition, please note if you purchase debt-financed real estate with your IRA, unrelated debt finance income tax should apply to the income attributable to debt-financed real estate held by your IRA.

It is hard for new guys and even people like myself to grasp how important those attributes really are.