Buying and Developing Land - Novice Looking for Knowledge

[Jin Nguyen]

Hello my name is Jin,

There is an opportunity to buy a 7,000 sqft piece of land.  The land is zoned for residential and a duplex is allowed on the parcel.  I am looking at this investment as a long term hold. Looking to just rent the duplexes rather than sell right away.  I am novice at all of this, but I need to get my feet wet somehow.  However, I want to enter this with as much education as possible.  Questions:

#1 - What are some good resources to examine to learn about the process of land development?

#2 - How do I value the land to determine whether the price for the lot is too high?  Do I use the residual land calculation?  Are there sources available that I can research to determine what the cost would be to build a duplex?

#3 - Should I speak to a city planner to make sure I know what the restrictions are before I purchase the land?  

#4 - What questions should I be asking?  As a novice I am not sure I am asking all the necessary questions to determine all the risks involved in this foray.

I am open to receiving any advice from people more knowledgeable to me.  I appreciate any advice and assistance.

Thanks