If you just look, for example John talked about SouthPointe and the benefits of those systems and information and processes that are brought to the Crown Castle business from SouthPointe. I was talking to John about this a couple of weeks ago. I said, John, how long did it take you build that. He said, three years. Well, that's behind them. They've had it for three years now, four years. We're just beginning down that road so that's just one example. There's many other examples on the operational side that punctuate the point of acceleration and probability of success for us, but from the combined companies I think in this case one plus one does equal two and a half for a lot of the reasons we've been talking about.
David, with respect to the other two questions, you asked a question about the master lease agreements that both companies enter into with their customer bases.
Certainly every one of the site leases that have been entered into to date under those respective master lease agreements continue to be governed by that original master lease agreement. So the carriers are otherwise not concerned about any specific change in that element of the relationship.
What every company that goes through one of these things does is we then sit down with the customers and we arrive at a new master lease agreement, in effect integrating from the one that perhaps Global has into ours or some variant on the two, reflecting the new pro forma tower company and what the opportunities are and how we and the customers otherwise look at things in that particular regard. So we'll be working on that over the period.
Certainly at close, the agreements that would prevail would be Crown Castle's. There's no specific change of control perspective in the Global Signal agreements, but we'll be sitting down with all of our customers and working on that as an opportunity, quite frankly, as we look to increase leasing with them.
Finally, I think if memory serves, there's about $275 million NOL within Global Signal give or take and against our $1.8 billion so, David, as we go forward it will obviously be added in and we'll not be a cash taxpayer for some time in the future.
With purchase accounting you basically value these assets and put them on the balance sheet and then start the depreciation over. Frankly, we haven't gotten to that point yet of pro forma-ing what the tax position from a GAAP net income or loss looks like, but suffice it to say we are still a number of years out from paying cash taxes.
Alright, guys. Thanks much. Congrats.
Thank you. We have time for one final question. It comes from Lale
Crown Castle International