What should we prepare for in terms of IP before talking to an investor?

One question they will probably ask or want to know about is how you are going about protecting your IP? So, if your IP is patent oriented, you can at least file a provisional patent application - it is relatively inexpensive for the USPTO filing fee, but ensure that the disclosure is as complete, accurate, and thorough as you can make it because it will serve for your later-filed non-provisional or PCT patent application. A provisional application is never examined and will never lead to a patent in and of itself - but if the disclosure is complete, accurate, and thorough, it will serve as priority for the later-filed application and so you will get a filing date and priority as early as you can possibly put together and file the application. Investors/VCs like that. If your IP is TM oriented, do the same thing - start the TM registration process. Consult a patent and/or trademark attorney.