This is a great question. While using a paid service to populate your reviews might seem like a quick and inexpensive way to hit the ground running, this is a path you should avoid.
Consumers are savvy. Fake reviews are easy to spot. If people notice that you are using fake reviews, any gains you may have made in rank will be offset by the negative opinions that the use of fake reviews will generate.
On top of that, if your fake reviews get reported to Google, your Google My Business listing may end up getting suspended. You don’t even have to necessarily get reported--Google may sense something fishy all on its own.
A suspended GMB listing will result in a huge reduction in traffic and will slash your revenue. Using fake reviews is not worth it.