double down rules, do they vary a lot between online casinos?

been playing a lot of live dealer lately and i keep running into different double down options depending on the site. some only let you double on 10 or 11, others let you do it on anything, and i’ve even seen ones where you can double after a split and others that don’t allow that at all. i usually stick with games where i can double on any two cards, feels like that opens up more legit plays.

i don’t really see a standard here and it kind of messes with how i decide to play certain hands. i get that each place sets their own house rules, but sometimes even tables in the same lobby have different rules, like the min/max bets stay the same but suddenly you can’t double after splits. want to know what people usually do to adjust, if you just move tables or play through it.