PPA? Patent? licensing for a royalty check

Hello I'm new to this site and got a great reply from them and they reccomended me ask on a forum.
I thought of my idea
12 years ago while working as staff at a Hospital, and I still do, this
product I thought of , I have not seen in 12 years, I have searched US
patent site, google and several catologes that my hosp buys products
from, nothing even close to my product. My product actually slips onto a standard use product, The product a standard in all Hospitals and has several other "disposables" that attach to it as well, My product is also a "disposable" .
Would I market the Company's that sell The disposable plastics, or the Company that makes the standard use equiptment and make it and improvement to the product?
I'm not looking to make millions even tho it would be nice, I am
looking to make a difference in the safety of my patients and allowing the
staff to do a better job without mistakes.

What I have done so far is made a prototype and tested it (works like a charm)
I contacted a prototype company and they wanted 575.00 to 900.00
dollars just to do a CAD sketching in 3d of my product..... heck with
that, my neighbor is an engineer and doing it for free!

I have taken all the measurements to make sure it is optimal size and
tested, so as far as a company making a working prototype for me...-No I have not done that, but my
protoype cost me a few bucks and it works great.

licensing it for a royalty check is the way I
want to go.

So do I still do a PPA?

Where do I file for that?

Then hire a patent search company? Who is best and cheapist?

Do I still need to wait a year to patent?

How much does a Patent final cost?

Can I do it on my own?

Once If/when I get a patent then I approach company's?

Thanks Again
Chris

Most of your answers can be found at either uspto.gov or rogerbrown.net I would also recommend reading Stephen Key's book One Simple Idea.