Yeah, yesterday was good time to buy as lately its started to rise again, so I don't think today is the right time to buy as price is comparatively higher.
Today is also a very good tme to buy some coins as the price now is not much higher, it will continue to rise more especially in the time of halving which will be in the next month.
If you are confident that price will be around $800 at halving, then you can still afford to buy at current price, as of now I don't have more money to invest, so I am holding my coins for halving.
If you buy at a high price, you should look for information, whether most people predicted prices will increase, more precisely you can find on twitter, usually there are some who always has a good predictor. although it does not guarantee a very precise.
Its just an speculations of people and to be honest no one knows what will be the exact price of bitcoin at halving, sell your coins when you are comfortable with price, don't follow the speculations.