Strategies for how/when to trade sciences

[Exsanguination]

I was just playing as the Americans and I came up with this problem:

I really needed banking so I could reel in the cash, but I needed cash to get banking in less than 15 turns. So I went off to trade Engineering to all the other civs. First off, the Egyptians offer me their World Map, 13 gold/turn and like 10 gold for it. It was worth it, for my current state. so I accept. HOWEVER, I had recently bankrupted most of the civs trading them the Republic about 10 turns earlier, and no one else offered me gold per turn. They all offered their World Map (which was worthless, since I had already discovered the entire world) and about 5 gold (everything they had). I know if I don't sell to them, the Egyptians will sell it to them instead. Should I wait, sell anyways, what???

And also, what other strategies could I use to get extra money?

 

[SteveLS]

Might as well, they'll get it otherwise. If they offer next to nothing for it, consider giving it to them, to sweeten their attitude towards you.

Other ideas for cash:

Sell luxuries to warring civs, as soon as possible....once they've been fighting for more than a few turns, they're usually broke, and won't give much for them.

Ditto for tech advances.

Sell worthless captured cities....pre-patch. For some reason other civs are almost always willing to dig deep for them.

Build lots of roads....and later railroads.

If you've got a luxury that many other civ's want, shop around and see who'll give you the most for it.

Ditto for strategic resources.

Disband units that are both obsolete, and non upgradable.

Don't build city improvements you don't really need. (like courthouse in the capital....harbors in all coastal cities....airports in every city). Which also begs the question....is a coal plant worthless if you have the Hoover Dam, and/or Solar Plants?

You might have to pinch pennies early on, but by the later stages of the game money is a lot easier to come by.