So when I registered all these domains they were something like $1/year, but to renew they are something like $10/year. Is there anything I can do to renew these at a lower price?
You can contact their support and ask for any possible discounts for bulk renewal. Hope it will help you to save some money.
Yes, domain renewal can be a pain if they comes at the same time. Maybe you can renew in advance next time round to even out the cashflow, especially if you many domain. The other way is to leave the least performing domains expires and re-register them later (at the risk of losing them).
I think you need at to have min of 50 domains to get a better deal from GoDaddy. it is always recomended to contact them by phone and ask for a deal. and also look or ask for a 30% off coupon.