Looking to give a shot for an early seed funding. So would having rendered specs design of a prototype be enough or an actual bench mark model is propose to be a good visual. Obviously the numbers have to make sense with an ideal ROI for the investors but visuals is what I concerned about.
I would suggest that you are not likely to succeed in raising early seed funding, except from people you already know very well.
While raising funding before your product is commercially available does sometimes happen, it is less frequent for physical goods or hardware devices and when it does, it's backing a team with a very strong background of relevant success. Increasingly, early-stage funding for hardware and physical devices happen through crowdfunding and I would suggest you explore that as your first source of outside capital. This also is a crucial step in market validation which will help with fundraising down the road.
I've written many answers here on Clarity about early stage fundraising so would encourage you to read my existing answers and if you'd like to book a call to discuss the specifics of your situation, I'd be happy to do so.