I do not think it is a good idea to buy now because the bitcoin price keeps rising.
If you already have bitcoin you can sell now and wait until it decrease again then buy back.
Isn't that contradiction?
If you think bitcoin price will continue to raise it can only mean that it is good time to buy and not sell.
OP i don't know what do you expect from answers, make your own choice:
1)If you think bitcoin will raise - buy it
2)If you think bitcoin will drop - sell it.
The rate of bitcoin is increasing with time and this is because a big investor have start investing in bitcoin now and also the users of bitcoin is increasing due to which the rate of bitcoin is increasing.