I  want to know that is it possible to form ?sole proprietor corporate
business? for real estate  in the United States of America country and
if that is possible then what  should be  the ?minimum?  amount of US
Dollars business of real estate  so as to form that mentioned  sole proprietor
corporate business ??

Yes, it is possible to form a sole proprietorship in the US for the
purpose of real estate.  Forming a sole proprietorship is very simple,
and only requires enough money to pay for your business license(s). 
Depending on where you want to do business (individual state(s) or
nationwide), you may have to pay fees in each state (and possibly
county and city).

Your first step is to apply for an EIN with the IRS (this is a good
guide to working with the IRS
http://www.irs.gov/pub/irs-pdf/p583.pdf).

Next you must decide which states you want to work in, then file for
business licenses in each.  This is where you'll spend most of your
time (because the forms for each state are different).

I should also mention that, depending on what you want to do with real
estate, you may have to file for other licenses and permits.  (Here is
another good website that explains this
http://smallbusiness.findlaw.com/starting-business/starting-business-licenses-permits/starting-business-licenses-permits-overview.html.)

After that, you may need to register your business name (additional
fees, usually about $50 per state, but not required in each state).

Just to give you an idea, if you want to work in one state, you're
looking at about $100.  If you want to work in the entire US, well,
that's a much more complex answer.

So, if you have money to get the licenses and permits, that's all you
really need.  The liks I included should provide you with a basic
understanding, and expectation, of what it will cost--depending on
where you want to do business.

I hope that helps

If you're planning on real estate investing, talk to an accountant.
Many/most real estate investors set themselves up as LLCs (limited
liability corporations). Some set themselves up as Subchapter S
corporations; there are some advantages and disadvantages to both.
There's no minimum amount of business you need to transact or dollar
value of real estate. You can set those up online for roughly $500 or
less. A lawyer may charge you a bit more.

Q: I  want to know that is it possible to form ?sole proprietor corporate
business? for real estate  in the United States of America country 

A: Yes, it might not be the best path, but yes, you can set yourself
up as a sole proprietor for this.



Q: And if that is possible then what  should be  the ?minimum?  amount of US
Dollars business of real estate  so as to form that mentioned  sole proprietor
corporate business ??

A: There is no minimum US Dollar amount.  You can do $1 if you want. 
But you should start with as much capital as you think will be needed
for your first deal and work from there.