If none of these resources will work for you there is one final option. If you have valuables such as jewelry, antiques or stocks that are not a part of your retirement portfolio, and you are willing to part with them in order to fund your invention, you can sell them. We would only recommend this course of action if you have no other. Exhaust all other possibilities before selling off your valuables.
You can see that while there is funding available for Shoestring Budget™ inventors, there is no magic panacea. It is, instead, a common sense approach to creative ways to fund your invention. You can help to make up for limited funds by careful planning and cautious use of your limited resources.