my advice will be to wait a bit. I guess the price will go down in December and then go and buy it 
Its a wild guess. I don't feel of having a huge dump by December, instead we hope it will continue increase and reach for $7k maybe. Not only the price today is the basis of having investment but we must consider also a possible to happen in the future. Even though bitcoin price is very expensive but still is an earning investment. We should not be worry of having dump because that is bitcoin really is and it will back again.I think price will go higher at the end of the year as we witnessed the same thing last year and price went above $1000 so history may be repeated once again and this time we will see price touching around $7k to $8k at the end of the year and if it does then I am sure majority of people will start selling their coins to grab huge profits on their investments.