I have an opportunity to purchase a 15 acre tract of land in a great location for a subdivision.

She felt that I was giving her quality info in a easy to digest format.

That meant that if Sonny and Cher took title as Joint Tenants, they more or less owned the entire property together—however, if either one of them passed away, the title to the entire tract would pass to the other immediately as an operation of law.

The house will be of the same quality as the typical OC tract homes in the market (i.e. average quality).

Is it "Lot XX of Tract XXX" or "Undivided 1/XXXth interest" ?

I need a quality software to track monthly payments, keep tract of current balance, and send out reminders by email.

Buy 20-40 acres on the outskirts of town, subdivide into smaller tracts and build single family homes to sell?

While Andrew Johnson's point is valid when dealing with larger tracts, here we are dealing with a 1/4 acre with an apartment building on it.  

Each program will work as long as you put the time, energy, and effort into digesting the training properly.

This page provides access to the property and tenant level data and also to data on Qualified Census Tracts and Difficult Development Areas designated by HUD.https://www.huduser.gov/portal/datasets/lihtc.html