you must look into a lot of aspects but the main ones are
1) team (real or not, investigate)
2) whitepaper
3) product (finished or not)
4) use case for product
5) cap and token sale details
I am sure there are few more but those are most important
1) team (real or not, investigate)
2) whitepaper
3) product (finished or not)
4) use case for product
5) cap and token sale details
I am sure there are few more but those are most important
To add to this:
6) Does the project require a blockchain or is just a money grab
7) Is the project unique or is just another clone of something already out
As for as profit if you only want to make 10-20% if you get in early you can dump as soon as they hit an exchange.
If you want to make 10x roi you may need to wait 1 year.
You can also just wait for it get on an exchange and wait for it's price to drop, the price always drops, and get it at a discount.
FYI
Full disclosure I am the CTO of the BlockRx.com project. ICO live now.