Tax Appraisal vs. Bank Appraisal vs. Real Estate Appraisal

[Nick Coble]

I'm analyzing my first deal. I have one rental currently. I bought it as my primary home in 2008, and relocated in 2011. We decided to keep it rather than sell as we had no real equity in it at the time. I don't count this as my first actual deal.

I live in a rural area. My closest "big city" is an hour away and still only has a population of 50k.

I thought I'd buy a few properties locally first and start branching out from there. My goal is to start with immediate equity in a house so I can snowball quicker.

I found a non-listed property that is already rented inside the city limits of my home town, population 4k. Using a line of credit on other assets, I could make a cash purchase on the house for $18k from a local "slum lord" slowly selling his way into retirement. County Assessors public records say market value for the tax appraisal is $28.8k. Zillow.com shows Zestimate range of $35-53k. Realtor.com estimates value @ $67.9k. Can I realistically expect a bank to appraise the home $40k and loan $30k from these #s? 

My hope's are to buy it and immediately turn around finance it (hopefully without any real improvements). Pay back LOC to $0 set back property reserves and have a fair lump sum to add to LOC to get the next bigger and better deal, scaling up each time.

Does anyone have experience assessing some of these values? In comparing the rental I already have, County Assessors public records say market value for the tax appraisal is $58k. Zillow.com shows Zestimate range of $78-89k. Realtor.com estimates value @ $103k. At one time the bank financed $72k. Using this comparison I feel comfortable with the above deal, but was hoping for some experienced feedback.