An ICO literally stands for Initial Coin Offering. If you are just looking for investors for a construction business I highly doubt you would need to call it an ICO because doing so entails the use of blockchains and cryptocurrencies. Doing otherwise would probably just brand you as a "scam" in the eyes of the crypto public. I say probably because it would still depend on how you good your business and marketing plan is. Good luck!
Right, but can your prove where an ICO entails the use of blockchains? I get it has 'coin' in the acronym but I believe that it doesn't have to include blockchains for it be legit.
Like you said business and marketing plan seem more important. From my expierence looking at ICOs it seems a lot of the whitepapers include broken english, bad math, a russian board of directors and contact information that is usually the business adress in some random country - most ICOs are a scam.
Therefore, I believe that if you can present a solid ICO idea with a good business plan then blockchain or not people will believe in the idea. Agreed?