Red Dead Online may not be a straight up RPG, but it definitely incorporates a lot of RPG elements. If you've ever played any other game with levels or ranks - and you'd be hard pressed not to - you're familiar with the system and its benefits. However, this week there are even more rewards in Ranking Up than usual, alongside some discounts on in-game items.
However, you need to buy these using RDO$ or Gold after they're unlocked - except in the case of a few items this week.
Each 10 Rank milestone starting from the very beginning up until Rank 60 unlocks additional bonuses beyond the usual rewards. This bonus is aimed at new and newer players, so if you already passed Rank 60, you'll get a Free navy Revolver, 5 Mash Refills, a 50% discount on Stable Stalls and a 40% discount on a camp Dog. The other bonuses won't be unlocked for you - though you probably have them already.
At Rank 10, you'll get a free Hunting Bow and a 5 Gold Bar discount off the Bounty Hunter License price. At Rank 20, the rewards include 50% discounts on a shotgun and revolver of your choice. Upon reaching Rank 30, you'll get a free Machete and 50% on a repeater of your choice.
Hitting Rank 40 earns you a 40% discount on a Stable Stall as well as a 40% discount on a horse of your choice, to have something to put into that stall. Players who unlock Rank 50 this week earn what is arguably the best of the rewards - a free Character Appearance Change. There's also a 50% discount on any Coat under Rank 15 as well as a 40% discount on a Tent of your choice.
If you're nearing one of these milestones, get a move on and rack up that XP. Unrelated to Ranks, all ammunition for Revolvers, Repeaters and Rifles is discounted by 40%.