A common situation for me on deity is to have a massive economy but no scientific buildings. I can reasonable buy techs or steal them and trade my way up the tree, but sometimes the prices charged are exorbitant. Most commonly these scenarios are where only 2 other civs are researching and trading with each other and I can only buy from them. I was wondering if it's better to just self research instead in those cases. I had a recent game where I had 10k gold saved and ready to trade, but I tried building libraries and universities and self researching. I could get a tech in 8-9 with a reasonable deficit but what I discovered was the ai would research at the same speed or faster. When researching I was deficit spending around -100 gold, while with Max interest I could accrue 500-600 a turn. I don't want to pay the ai 4-5k gold per tech and fuel their research, but self researching just bleeds money with the same result, at least for me. Stealing techs is risky because of war and losing luxuries, although steals are half the cost of buying techs. I was wondering what other players did in this situation.