It would seem you are a bit conflicted as to both the propriety of P4P, as well as the health and monetary issues. These are two very different things.
As far as health goes, do as I do and use a cover for ALL activities, and you have eliminated 99% of your concerns in that regard. That's not to say that you don't risk being discovered by your SO, arrested by LE, or getting ripped off. Nothing in life is ever completely safe, but you can take reasonable precautions, particularly by sticking with well-reviewed ladies.
Now for the propriety part: Not to put too fine a point on it, but you are contemplating paying for sex. You know, providers, hookers, prostitutes, whatever term you wish to use. With yourself as the "john!" You won't be "boldly going where no one has gone before". The provider is experienced and skilled because, well, she has had plenty of practice. Its my understanding that so-called virgin provider are available in some other countries, with Filipina B-girls coming to mind. But that's a long way to go to buy a new "car", as you put it. If the thought of being the 50th, 100th, or 500th guy the provider has been with bothers you, then don't cross over the line into P4P. Of course, you can have that same problem with civie girls, too.
Finally, you reference dollars. This is not a hobby for those with limited funds. If spending 5-10 (or more) dollars a minute for the company of a beautiful woman causes you some concern, consider that other hobbies, such as coin collecting, muscle cars, high end travel, golf, and fishing, can easily cost as much. And I've never blown my load all over one of my Corvettes.
Yep, "these are the voyages..."