Ruling on ● earning husband and earning wife contributing money for 1 sheep for Qurbani . ● wife and husband doing 2 seperate sheep for qurbani ● Ruling on fasting Arafah first then fuflilling obligatory fasts .

One Udhiyya is enough, and you can participate if you want to in paying for it. As for fasting Arafah while needing to make up missed fasts, do not do that. Some of the scholars have said that it is invalid to do so; your fasting would be invalid in the first place. Therefore, make up the obligatory fasts that you need to complete first.