I am looking to refinance a duplex that I purchased in July using an FHA loan, and am trying to get an approximate idea of whether or not there is enough equity to refinance into a conventional mortgage. We paid $163k and the house originally appraised for $186k. We have a loan balance of ~$158k. LTV based on the original appraisal is therefore around 85% -- not enough for a conventional refinance.

Since purchasing the house, we've put over $20k of work into it; unfortunately, some of the big ticket items are non-contributing improvements (e.g. we found out after closing that one of the furnaces and both water heaters needed to be replaced.... home inspector apparently wasn't as thorough as he should have been). One project that might add value was the construction of a curtain wall that subdivided a large, awkward bedroom into a nice MBR and a new fourth bedroom with a large reach in closet.

In reviewing the appraisal, I noticed that the appraiser had observed the existence of the attached one car garage, but missed that the property also has significant driveway parking and a detached two car garage. I imagine that the inclusion would have driven the estimated value even higher.

Obviously a new appraisal would be required for a refinance, but I don't want to go through the time, paperwork, and expense if I'm not confident that the property will qualify. Does it seem reasonable to expect that turning a 3 bedroom into a 4 bedroom and "adding" a 2 car garage would yield the 11.5k needed to get to 80% LTV? For further context, one of the comps was a 4 bedroom, and the fourth bedroom was adjusted out at $6k. The one car attached garage was adjusted the garage-less comps upward by $5k, so I would hope that a 2 car garage would be worth a little more than that.