How can we launch quickly and secure IP at the same time?

One way in which you can begin to protect your IP, particularly patents, is to file one or more provisional patent applications. Provisional patent applications require significantly less cost to actually file, that is, for example, the US Patent Office, but the content of the provisional patent application has to effectively be as good as a non-provisional patent application because the provisional application will serve as a priority date basis for your later filed non-provisional or PCT application. So, if your invention disclosure is truly good in that it truly discloses your invention in a clear and complete manner, you will be OK and you can file that disclosure as your provisional application, even though it may not technically be in the proper patent application format. But this should really not matter because the provisional is simply filed to provide the priority basis for the later filed non-provisional or PCT application. The provisional application will never be examined and will never lead to a patent in and of itself. Plus, you have to remember to file your non-provisional or PCT application within one year from the filing date of your provisional application. On the other hand, if your disclosure is not a truly good and enabling disclosure truly disclosing all important aspects of your invention, then you probably need to have a patent application professionally drafted.

As Steven wrote, the disclosure of a provisional application has to provide a solid basis for the patent applications that will rely on it. A properly-done prior art search will give you an idea of how applications for similar inventions are written. How wide and thorough your description should be (it will also help in emphasizing the differences between your invention and the prior art).

Both of the previous answers are correct, from a technical prosecution point of view. However your question was, I believe directed to "have its IP secured" in order to "secure serious funding." Simply filing a provisional will protect you with a early filing date and is always a good idea. However, it will not help you secure serious funding. Investors want to see an issued patent so they can assess the extent of protection. You need to file a non-provisional as soon as possible and follow it up with Continuations-In-Part as you make changes/improvements. This will get the process started, as opposed to a provisional patent which is simply an idle place holder. In addition, you will want to use one of the many avenues for accelerated prosecution. This will unfortunately add cost, but will significantly shorten the often three to four year process of obtaining a patent. Momentum is important, the USPTO recognizes that and charges a premium.