Ask HN: Should we raise more money?

I am in my first round of funding and about to close it.

Background: We are working on the project since 1 1/2 years, 4 founders - living in different cities

Status: Prototype - ready for launch approx. may 2012

We have 2 offers from angel investors:

1) 10% - 140.000 EUR Really good Angel, has perfect network and experience in our field of business

2) 3% - 42.000 EUR Is a privat person - medium network and expertise - more "dumb" money

Our expenses for the next 12 months are at least 115.000 EUR

If we would move together and live in a appartment together in berlin, it would be 133.000 EUR

We plan to launch in may 2012 in cooperation with some of our clients for beta testing (no revnues).

We plan to make our first buck in october 2012.

Questions:

1) Whats a good way to calculate the amount of money needed - e.g. expenses of X months + ??%

2) What should be the end of our current runaway and current goal to raise the next round - launching? revenue? growth?

3) is it very negative to have small angels invest in you with just 3% shares for further funding rounds?

4) Is living together worth the money? (2000 EUR/month)

Thank you very much for your opinion!