Are these floral prices reasonable?

I think you could go to your Mother in law and just be honest. Say you really want XYZ as far as flowers go, and that the price is $1800, but you would love to split the cost.

I think that these flower prices are reasonable given the current situation for flower farms and florists in general. Due to Covid there is way lower stock in a lot of flowers but tons of demand with everyone rescheduling their weddings, and therefore their wholesale prices have gone way up (at least this is the case for all the florists I know in my area, which is already higher priced for things). I agree with what a lot of other people have said, I would be honest with your MIL about the price and say that you want to go with this florist but don't feel comfortable with her paying for the whole thing and would like to pay for half (or however much you wanted to cover). Of course you can still look around for other offers too, but this price seems consistent with what I've seen.

I think that these flower prices are reasonable given the current situation for flower farms and florists in general. Due to Covid there is way lower stock in a lot of flowers but tons of demand with everyone rescheduling their weddings, and therefore their wholesale prices have gone way up (at least this is the case for all the florists I know in my area, which is already higher priced for things). I agree with what a lot of other people have said, I would be honest with your MIL about the price and say that you want to go with this florist but don't feel comfortable with her paying for the whole thing and would like to pay for half (or however much you wanted to cover). Of course you can still look around for other offers too, but this price seems consistent with what I've seen.