Purchase should be ballpark of 50k provided your ARV and renovation projections are accurate. 

When you're confident that you can estimate cost fairly accurately and quickly, do the homework and run the numbers FIRST, then make an offer.

Not exactly what you were asking, but I wanted to give you a little of my perspective.I wouldn't model using the Zestimate, as it is very possibly not accurate for a home in that price range.

So It's gonna be a gamble if I decide to sign for a new one year and let sec 8 decide what the rent should be.In this case the tenant pays only $55 per month.

I’m going to assume you’ve done your homework and that your numbers are all accurate.

Now my bank said I have the option of paying for a full appraisal to get a more accurate value.

The quickest, easiest and only accurate way is to simply get preapproved for a loan.

This is where you compare features (such as garages/pools/beds and baths etc.) of the subject property with the comps, assign a dollar amount to those features, and then adjust the sales price of the comps up or down as appropriate before calculating the subject's ARV based on those adjusted comps.This will hopefully help you nail down a more accurate ARV for your property.Feel free to reach out if you have any questions.

I'm not saying the numbers are necessarily accurate but the method is.If you have a $100,000 capital expense coming 10 years from now if you put away $833.33/mo for 10 years you'll have saved enough to pay that $100k when the time comes. 

My next purchase will be in this area off Union.I find the https://www.biggerpockets.com/renewsblog/guide-grading-indianapolis-neighborhoods/ guide to still be pretty accurate - even listing the right C+ areas nestled between C-/D neighborhoods on the eastside.