Multi-units appear to be in demand more than I've ever seen in my 16 years. 

Rents in the $900+ range, $700 range for MF as well as pretty high demand for retail and office spaces.As others have stated as the market continues to improve the cost to acquire these properties is continuing to rise.

First, I really have a hard time believing that rental rates have increased that much over the last several months even though that is what all the evidence is telling me.Second, I'm debating jumping it up all in one year or doing something modified.I know that single family homes for rent are quite difficult to find in our area and in high demand (we get contacts regularly looking for something like this). 

I'm assuming there is lower demand in May-October timeframe?  

Demand would have to be constant (stagnant) for supply shifts to explain 100% of market price. 

Supply and demand, my friend.

Given the current market demand I'm not seeing many options in a 20 mile area.

Good weather + plentiful high paying jobs = high demand.

The need for high quality land to meet the global demand for food now and into the future, will remain high.

In high demand area, can definitely be rented out almost immediately.