Patenting Costs article: How much does it cost to get a patent? $5-8k total (US Patent issued), depending on what kind (design or utility), how complex, and in which countries patent protection is sought.
The first step in seeking patent protection is to find out if the invention is patentable. The first step to patenting has two connected parts. A prior art search, and a patentability evaluation.
The basics on how to start and conduct a prior art or patent search to find out if an invention is novel and non-obvious. By Carson Patents, USPTO Registered Patent Agent, Gregory Carson.