You are almost there, but you are not quite done with the finished product. You might be able to tell the difference, but it is your job to also be sure that your client knows the difference between a rough sketch and a final rendering. You can keep your numbers soft as long as you maintain an upbeat attitude. Let the user have a voice in a technology decision. The more people you get involved, the less likely you are to be held responsible for anything that may go wrong.
You may want to don your soldiers uniform, because the Universe has declared that whatever you are trying to accomplish will be a struggle to the bitter end. Whether suffering in silence or going down in a blaze of glory, you still end up on the bottom. Instead of feeling sorry for yourself, try to look beyond this point. If you manage to form even one alliance this time, it will all have been worth it. The lessons you take away from this experience make this day historic.