So, I hired a landscaping company here in the Boise area to install some curbing and a sprinkler system in the backyard of my property.  

This place has the education, network and willing participants to really help boost your game.

Finding a property that is stuck in time that an update will boost value and marketability is key. 

None of the pics say "wow".Also, many tenants in urban areas want to see the outside of the building, so curb appeal is a positive.Also, what is the title of the ad?

That's your choice.Then I'd talk to a Landscape Architect and have the person come up with some curb appeal ideas, and then get bids on that.If the total cost comes in below the per door cost to move forward then it "MIGHT BE" a go.I believe looking at each unit as one job to be completed is more intuitive than looking at the whole complex as a job to be completed. 

Of course I could advertise and take applications while under construction.Second question is how would you determine your absolute best offer price on a building that is 100% vacant, with competing units in the area that are newer and have much more curb appeal?

I'd also like to echo the sentiment of others in saying that it would be better if you just invest in a REIT or CD (chosen based on your appetite for risk) until you're back...BUT, and this is a big BUT, I feel that instead of investing money over the next 3 months, you should invest your time into learning about REI & read books that will help give you a great confidence boost and "success mentality".

The fact that you only had to put 5% down really boosts your return on cash, which is the metric I like to look at, looks like around 12.5% and 19.5%. 

Sounds like a fair deal if it's near to where you live so you can watch and maintain it.Does it have good curb appeal?

In 15+ years of real estate experience, reviewing more than 10k houses, one gets an eye for a few details.The touches on this house look nice, good curb appeal.