What kind of research I can do with my data set?
There are several things that can be done, however as @Dawny33 mentioned, start with the problem you want solved. 

As an example, If I was trying to solve: Which factors, influence the prices and how?

A simple analysis could be to run a linear regression model (lm) with PriceSqFt as a dependent variable and others as regressors. You can then select top 10 or 15 or how so ever many you like and look at their relationship.

This may help you answer some simple questions like: 

How do prices vary by dealers, by property type, by location, by size?
Does move in ready date make a difference to rent / prices?
Do specific kind of properties have later than usual ready dates?
Is there a negative or positive correlation between size and pricesqft?
Are certain dealers over or under priced compared to other identical
properties and location?  


You can also create a plots using pairs or other functions to look at pairwise relationship for initial analysis and building on top of what you see.

If you really want to take it a to the next level, you can create a prediction model to predict the price based on select parameters.