paid the back taxes during the redemption period - would they become the sole owner or would the remaining heirs still have a claim?

Is this something to completely avoid?

Any idea what the minimum requirements are to claim something as a primary residence?

They claimed they have better chance to get the to-be auctioned properties from county. 

Hi Darius, Yes, you could buy property B and then refinance the property to generate additional cash to complete the acquisition of Property A. 

If they have some bogus claim that they are using to 'get out' of the lease easier/cheaper to let them.

Curtis is completely right!

The upside is regarding the construction loan is you can capitalize the interest during construction increasing your basis in the project, The downside is you will need to bring a decent down payment and if you don't own the land or have any construction experience, and you'll need a partner with developer experience especially if this is your first project.I would recommend a JV with a developer, maybe a reduction on the developer fee in exchange for something on the backend of project completion, there are a few good ones out there that do small projects as well.

E.g. if payroll is in $1100-1300 range but T12 claims it to be $500, use the number from the range.Hope that helpsNick

This would not prevent your debt to income ratio from being too high, because the mortgage would initially be in your name the banks will still view this the same.Lastly, the six figure bracket is not always as easy as it seems in real estate because things will come up that you completely did not expect and take a huge chunk out of what you're expecting.