What options do we have if my mom passed away leaving me, my brother, her half-sister, and grandmother as her closest relatives with no will?

She'd also been remarried for 3 years (though only 1-2 years legally due to a filing error of their marriage license). I live in the same state with my mother and step-father, however with the exception of their house here (which I believe they both were on the title) and a joint credit card account through their company. My mother's entire estate was in another state where she kept legal residence with all of her estate being under her previous name, only living in Indiana for missionary work (returning several times a month to help my grandmother and maintenance her house). Both my grandmother and aunt wanted their intestate shares to be given to me and my brother (with the exception of some furniture and a few trinkets) if they were supposed to get any. My stepfather made several promises to my family claiming we'd get everything with the exception of what it would cost for my mother’s funeral (about $17,000) if we made him executor. But lately he's remarried and hasn't been telling us anything about what's happening with the estate. He took her money out of her bank account that was in her maiden name (about $20,000) and kept all of it, paying the $17,000 to his company and keeping the rest. Also, he refuses to tell us how much her house (which was under a previous married name) is being sold for. He's given away almost all of her separate personal property (many of which he allowed his now wife, girlfriend at the time, to keep or give away), or sold it at an extremely cheap garage sale, and burned/trashed the rest of it without recording any kind of financial record or distributing the profits. We barely got any of it otherwise. It's been a little over a year and we've yet to see a dime.