I meant Uplink, not Nexus. My bad. Nexus needs to be researched and takes 21 days, Uplink is available from the beginning and takes 14 days. I edited to make me sound like less of a crazy person.
Getting a Nexus in the first month is a bit of a tall order, yeah.
I might just set the difficulty to Normal and save scum my way to seeing if its actually possible to have three new satellites in the air by the end of the first month.
According to UFOpaedia, base funding (not accounting for your starter country) is 100 on Classic, 200 on Normal. Starting in America will give you the best chance at having enough money for that first month. This would be moot if that starter country doesn't affect whatever amount of money you start the game with though...