At the VERY LEAST for any unknown service provider requiring money to be sent to them...google the name of the service with a keyword like 'scam' (or similar) to ensure there aren't any negative reviews already up on the internet.

When I first started to buy crypto I did the following:

1. Internet search on company name with keywords to ensure there weren't any negative reviews
2. A check of the company using a central register (available in the UK) to ensure they were registered and financially solvent
3. I prefer to work with companies which have a collection of good ratings via established third party trust sites
4. Even after having done the checks above I will ALWAYS perform a couple of transactions for small amounts to ensure I understand the process and that the transactions have been carried out in a transparent and timely manner

It's up to all of us as individuals to perform as much 'due diligence' as we can.