There are lots of different lists you can call and no perfect answer to "the first one" you should call.
A big factor is area. For example, probate leads are not ideal in California or Washington due to how the court mandates a probated property is to be sold.
However, Oregon is a phenomenal place to market to probates.
I can't speak on PropStream as I haven't used their platform in a long time.
However, vacant lists, tax delinquencies, code violations, probates, divorces, and evictions are all pretty great lists. If you're wanting to start with a broader list, I'd suggest putting together a list of High Equity Absentee Seniors.
I'd also recommend filtering your list, if you can, to include only properties owned by individuals.
If you need any help getting court records in your county, you can call the local courthouse to see how records are stored and what the process is to get these records.
Sometimes you'll need to go in with a laptop and record them manually..other times they'll have an easy search function on an online portal.
Driving for dollars to build a list is also a fantastic way of finding motivation. Plus, you can often talk to the neighbors to get the scoop on the property.
Of course, with any of these lists, you may need to skip trace to get current contact info. There are free resources online that are extremely hit or miss.