Mining - Getting Free Rack Space - Need Suggestions

[CpuPirate]

A little bit of back ground. I am not new to mining, I built an open air 6x R9 280x rig back in 2013 and mostly mined LTC to convert to BTC. At the time I was mining from home using about 2kw of power and where I live I broke even until the price of BTC dropped to sub $500. At that point I parted the machine out and recouped as much cost as I could and moved on.

Fast forward to today, and obviously the mining market is hot again and I started fun mining on my 1080Ti in my home rig when I wasnt using it, the power is pretty low and return is descent on things like ETH or ZEC. With that I have considered building up a couple of budget machines and just let them churn on probably ZEC, but not 100% on that yet. But alas I have been given some data center rack space (about 70u total) which will include the cost of electricity and cooling so that's no longer a concern. What is a concern is that I am limited to plugging into power only, which means I can not in any way use the network in the data center. So problem # 1 is how do I get internet to the mining machine(s). I have considered a verizon hotspot (they have verizon repeaters in the data center so signal is good) but I have no idea how much bandwidth I will need, I have seen that throughput is not high but total bandwidth for the month is a figure I need to know.

I am trying to keep this as budget friendly as possible, I know most people would jump at the opportunity to mine with free power, but ROI on just the hardware is super important to me.
I also have access to the "scrap" servers and PSU's from the company so I am going to look for some 4u chassis to hack up and 750-1200w psu's from the servers to power the cards
Probably going to get used or cheap 4-6 PCIe mobo's
I was thinking since the hash to watt ratio is not important I would be best to use 1080 Ti's as they have the highest hash rate and are still available?

TL:DR
I need internet connection in a datacenter separate from what they use. What is the bandwidth usage for mining typically?
What are the best GPU's to buy if you dont have to figure in hash/watt.
What is the best long term coin right now to point said GPU's at?

[dbc23]

To question one, it seems a 4 card setup is roughly 2-3gb data per month.  Although that's highly variable depending on algo and total hash.  Dagger algos seem to use more and higher hash will mean more shares.

I can say that I priced standalone cell data plans in the US and compared my residential electric cost to the cost of data assuming i could get a sattelite site with free electric but no data and it always worked out to be a complete wash in savings PLUS my rigs would be harder to access for maintenance and i was skeptical of cell data reliability.