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
^^ what he said. A good ico to look into would be the bee token. They are taking a working model (Airbnb) and perfecting it with blockchain tech. The best part? Zero commission. I hate using airbnb because of those fees.
https://www.huffingtonpost.com/entry/59e52b47e4b04e9111a3e442