Their city told them that if the shed sits on the ground, on a poured concrete slab, then it counts towards the square footage for the property tax. 

Commercial square footage rates are usually quoted annually.

@Gene Hacker   Lower square footage could also factor in. 

But it depends on the property sq footage and condition and the block. 

  $14.5K return on $145K sale price is about 10% return on ARV -- I typically look for a minimum of 15% and ideally closer to 20%.Since this is a big rehab -- adding a bathroom and square footage -- there are a lot of potential cost overruns and surprises. 

Maybe even more than they used to,The owners of the mall (who bought it for a song in bankruptcy) just submitted plans to demolish half the square footage.

The specifics and financials are below:3 Story Mixed Use BuildingTotal square footage: 4,920 sq. ft.1st Floor: Commercial Office Space - 1,400 sq. ft., 4 offices, reception area and conference roomCurrent rent - $650/month2nd Floor: 2 apartments - 700 sq. ft., 2 bedrooms, 1 bathroomCurrent rents - Unit 1: $650/month, Unit 2: $650/month3rd Floor: 1 apartment - 1,600 sq. ft. 3 bedroom, 1 bathroomCurrent rent - $800/monthTotal rents: $2,750Includes .26 acre build-able vacant lotInsurance: $4,400/yearTaxes: $12,623/yearAverage Commercial Lease in the area: $13 per sq. ft.

In North Texas, I've figured out my sweet spot for purchase is about $70/sq ft with square footage between 1800-2400.

I suggest looking at three or more recently sold homes (within last 6 months if possible) with comparable size, condition and square footage.  

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