You must understand that all of these private taxi drivers are smiling in our faces and are our "friends" as long as the money is rolling in. As soon as the money stops, or they get a better offer, see ya!!! Kind of like the hookers in that sense.
Honestly, they are all a bunch of scammers, but they kind of have to be in that profession. They always lookout for #1 first. Read this from a couple years ago to see an example of what I mean:
https://costaricaticas.com/phpBB2/viewtopic.php?p=118624
When I used to stay at SL all the time, and used their services, they were all my best friends. Now, they don't even say hi when we pass each other.
Mind you, these are private drivers, they are not employees of SL. Don't expect the fine reputation and customer service that the SL exhibits to carry over to these guys. They will leave you stranded and no-show if more money comes along.