if one server became two servers i would pay 10 USD per month renting costs instead of 5 USD but also the increase in masternodes (from 3300 to 6600) will automatically
force lower MN rewards for everyone, wont it ?
But you have now two masternodes instead of one.
and it will be a lot more easy for others to join the masternode market (first-timers) with a collateral of 500 Dash so in the end its reasonable to guess
the total number of masternodes will be more then those calculated 6600 .. driving the rewards down.
Anyways there is a lot of time to think about this, its totally not a problem yet.