I've read about how people NORMALLY get around this problem by setting up "forwarding" ports on their routers, but this of course requires that they have access to their router, which I don't. So would I need to buy a 2nd Verizon Wi-Fi Hotspot Device along with an external router and attach these both to my Windows XP computer that's in my apartment in order to make it work correctly as a VPN server? Would this be allowed by Verizon?...I mean, do these cellphone companies usually allow 2 connecting devices to be attached to the same Wi-Fi account from 2 different locations at the same time under the same account?
So this has been one idea that I've been having, although I don't prefer it. The other of course would be to somehow get my server-bound packets to pass through the apartment-complex's open Wi-Fi system on into my Windows XP that will always be maintaining an active connection into the Wi-Fi. I'm not completely clear on networking protocols and such, and so I was wondering isn't there someway that I can make my VPN client computer send the MAC address of my server computer in it's networking packets so that when the apartment-complex's Wi-Fi router receives them, it will know which active connection (my Windows XP machine) to forward them to automatically without having to program their Wi-Fi router? If anybody knows of such a thing (perhaps via "tunneling" of some SPECIAL type?), please let me know.
I have already tried using the normal simple set-up of Windows XP as a VPN Server via the Windows Connection Wizard, but the connection of course fails undoubtedly due to the apartment-complex's Wi-Fi router being involved. On the VPN-Client-side in my Windows 8 computer, I had set the IP address of the VPN-Server to be on the first time the IP that is found via the "ipconfig /all" command on the Windows XP computer regarding its Wi-Fi Adapter IP-Address, and on the second time the IP that is shown on the IP-lookup websites. Neither of these IP-address settings worked, with an error ("800" I believe) popping up in my Windows 8 machine set up as the VPN client during attempts to Connect, which I believe meant that the apartment's Wi-Fi's router was receiving and of course rejecting the VPN-Client's attempts to attach to it. I know that my computer's local IP address is invalid anyway concerning the public Internet's usage of IP addressing, so I wasn't really expecting it to work but nevertheless had to try just to see what would happen. Also, as expected, when I'm attached through my apartment-complex's Wi-Fi, the IP address shown on the IP-lookup websites is the SAME IP address for EITHER of my computers, EVEN if they are both attached to the apartment-complex's Wi-Fi at exactly the SAME time. This means, of course, that the apartment-complex's Wi-Fi Hotspot router is using some way of distinguishing which inbound packets go to whichever connected machines, this of course likely being the MAC addresses of the wirelessly-attached computers. But I'm not completely sure just yet how exactly this works (and would really like to know more about it). Perhaps the router builds an internal table containing its attached computer MAC addresses along with random numbers that it assigns each, and then sends the packets out onto the Internet including these randomly-assigned ID #'s so that when a return packet is received, it can then translate the number via its table back into the correct MAC address so that it knows which of its connections that the inbound packet has as its true inbound destination each time? Or perhaps it even directly uses the attached computers' MAC address-values as these sent numbers? Or perhaps these ID numbers are just the "Session" numbers, the router maintaining knowledge of what attached computer an inbound packet is destined for simply via the session number that remains during each open connection, with each session number being different for each device that is actively connected to the router at the time?
And so another idea that I was having about this kind of involves the concept of how the routers may be working perhaps having to do with open connection sessions and related. When a computer attaches itself to any website--which that website is then acting as a server--the router client then is likely doing so via holding-open a connection that it's made to that server (the website) that you've just initiated contact with (which is likely done via the session number, I believe), and this is likely why it is easy for the server to thereby communicate back with the client because it has this still-open connection at the time. On the other hand, when I try to connect to my Windows-XP computer via the Internet through the apartment's router, the router has no open connection to me yet and is only connected locally to my Windows XP computer, and this is likely the problem. So are there websites out there that can serve as VIRTUAL SERVERS for people that are in situations such as I'm in? A person such as me could simply connect to it with my Windows XP without any troubles whatsoever being that it would merely involve visiting a particular website address. The website address--acting as the server as they usually do--would then hold open the connection as long as the person needed it and would then assign a public IP address to the connection that could be used during the connection as a server for VPN'ing into effectively as a VPN-Server. This way both connections from both involved computers would be outbound and would therefore have no troubles getting through whatever routers might be involved. And I suppose both involved computers would set themselves up as VPN-clients with this "VIRTUAL SERVER" type of website serving as the VPN-Server for BOTH of them...or something to that effect. Do such websites yet exist? Is there anything PREVENTING these types of websites from existing if they don't yet? Perhaps this might even make a good business idea?

Anyway, the bottom-line to my inquiry here is to find out the easiest possible way for me to get my VPN set up to work within this type of an arrangement. And if I really must buy some additional equipment in order to accomplish this, then I guess that I can do so. So I greatly appreciate any help or feedback on how to handle this situation or on anything connected with any of these mentioned subjects. Thank you...