So you drill through floors/tiles/ hardwood and find that was not the location.  

I've been considering some basic hard wood flooring.

rehab came out to 12k including paint, tiles, hardwood resanding, some appliances, electrical updates (moderate). 

Work done includes refinishing hardwood floors, all new kitchen, all new bath, exposing original brick (who knew that would be one of the hardest parts!

Dated cabinetry.Bathrooms- Tile flooring, tiled showers, granite top single vanity sinkFlooring- Original hardwood flooring mostly still in good shape, possibly some leveling here and there.Siding- Needs paintRoof- Good shapeHVAC- Good shapeOverall the interior looks to be a little dated but an attempt has been made to update here and there. 

We put recycled solid surface counters and upgraded from carpet to hardwood and rubber tile for the basement. 

Things like carpet can easily be replaced with something better (tile or hardwood floor or vinyl plank flooring), or an odd color in the kitchen can easily be painted to look a lot nicer.

With your contractor during the walk-through or over lunch, make a list of all common repairs and get an average price per square foot.Ie, carpet is $4 per sf including installationRefinishing hardwoods is $x per square footI think roofers usually quote by the "square"....which means a 10'x10' section of roof (100sf).  

with a 2 car garage, a whole new update, hardwood, a 1.2 baths, yes, i will get $1200 easy.

Now for the numbers on the property:Property Description: Duplex with 4BR-2BA total, in a good area within 2 miles of local, large state university; exterior condition is good as it's brick with new metal roof, windows, metal siding on trim; interior has hardwood/tile floors, new ceiling fans, lights, appliances, and paintPurchase Price: $118,000Down Payment: $23,600 (with closing costs credit from seller, final number at closing was right at $24,000)Loan: Commercial loan 15 yr AM, 5 yr balloon, 5.0% interestMortgage: $750/moTaxes: $200/moInsurance: $80/moRent: $2,100 (rented to four college students as one group; tenants pay all utilities)Est maintenance/repairs/cap ex: $300/moVacancy: $100/moProjected cash flow: $670/mo or $8,040/yr (est. $4,200/yr in mortgage principal reduction)Amount spent on repairs: $15,000 (majority spent on new HVAC/duct system and appliances)CoC return: 20.6%I think that covers most of the relevant numbers.