They must sign the form.The IRS offers an online tool that lets you check if the tax ID the contractor gave you matches the IRS records.

However, the concept of a virtual office is a very useful tool that provides a professional fiscal and commercial address, as well as additional services such as mail handling, meeting rooms, and phone assistance.

Take advantage of the great learning tools it has offer.

We're on the same page with HELOCs being great tools.

Additional resources and tools via brokerage.... 

REISimpli seems like a decent tool from what I can see on it.

Be sure to check out the free tools BP provides to help analyze deals you may have and also market insights.

Not to find deals on the MLS but to potentially use the MLS as a tool to sell your deals.

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The online tools are a good way to get a ballpark number and can sometimes be close to accurate, but a PM is able to tell you a more accurate amount.