If you're not sure if you want to make the jump straight into resin there are other options before diving that far in! :)
For a couple years I was totally obsessed with Liv dolls. They're not BJDs by any stretch but they're the closest playline dolls have ever gotten. They have really excellent posing abilities, have inset eyes you can swap, and wear wigs. You could see if you can find one secondhand as a bit of a test to see how much you like the BJD-like features. They can even fit into Barbie clothes so if you already have Barbies you don't need to worry about that.
There's also ABS BJDs, which are just BJDs made of a different material. They're not allowed on some BJD forums but they're an excellent, affordable alternative to resin. All three of my BJDs (two Jun Planning Ai and a Hujoo Freya) are ABS. I've had all three for years and absolutely love them. If you can find an ABS doll you like that could be another step before you decide to make the leap into resin.