I found out about a workshop a few days before yom tov. As there will be a mix of a variety of attendees attending, I asked my Rav a shaila about whether I could attend. He said we should speak after Pesach. The early bird rate is $795, and it expires tonight. After that, the rate goes up to $995. After registering I will have 10 days to decide whether or not I would like to attend, IY”H giving me time to speak with the Rav before that time and after Pesach. Can I register tonight, even though it’s Chol Hamoed, since there’s a $200 difference inregistration cost?
You can register now, this is fine. Although it is worthy to limit one’s dealings on Chol HaMo’ed, it is permitted to purchase (and to “register”) where there is a need.