rent is not on that 350k limit (u can spend up to 600k a month in rent, which is enough for a pretty nice place - I currently pay 300k and live in the trendiest city in town)
if you're bringing family here, don't expect to be able to feed everyone on restaurants two times a day, every day of the week. That's impractical on basically ANY city, if you have a family. Alas, if you're planning that, you should not even be considering bootstrapping....
so, updating my back of the envelope math for the monthly costs:
~US$700 rent
~US$700 for 'living' (food, transport, etc)
~US$4000 for paying two extra junior programers
that will take you around 7 months to burn the 40k.
maybe 6 if account for the trip and initial set-up.
I'm doing my business plan right now and what you say is about right. Don't forget to have some budget for operating expenses - services like github, mailchimp, accounting program really add up...
Of course you can assume your revenue will cover those.
meal price * people * two meals day * 30 days
3k * 2 * 2 * 30 = 360k
other comments mention rent $300 (150~200k pesos?)