Let's dive into the 'card renting' markets with PeakMonsters card level bids.
Let's go over some examples of how to pick your rental prices. This works both for 'renters' and 'rentees', and we will be using PeakMonsters's card rental bidding system and data gathered from it.
This post is inspired by 
Thanks for the reply. I got to explore the PeakMonsters feature. And maybe the market rent prices doesn't treat some of my cards well, even if they're a bit leveled up. Two of the 'unpopular' cards that I was mulling over were Serpentine Soldier and Clay Golem. These were the top 2 cards for Best CP/DEC ratio. Good for rentees, not so good for renters haha.
Markets within Markets
There are really 2 (two) different rental markets in Splinterlands. There are actually a bunch more inside both of those, but let's get to the basics first... because with that knowledge you can dive as deep as you want.
This should be especially helpful for information about seemingly 'unpopular' cards as
the Rental 'Ranking Market'
The two main rental markets in Splinterlands are what I have come to call the 'Ranking Market' and the 'Power Market'. They are very different.
In this post I'm going to cover the first, the Ranking Market. I'll make another post to go more in detail about the 'Power Market' another day. Please be sure to let me know in the comments if that's something you want to see, the feedback helps me prioritize what to write about.
Let's get straight to an example with one of the cards
Jazz is right, this is not the most popular card in the game. But it's most certainly not at the bottom of the stack either. It's actually a pretty useful card. But let's take a look using PeakMonster's rental bidding system to see how popular it really is.
Zooming in, we see the best price, at the time I took this screenshot, for a level 1 is .313 DEC. In this case, I'm not so concerned about the CP/DEC metric, I'm interested in the DEC/Day rental amount.
.313 DEC is the listed rental price, but are there any takers at that price? Is that really what it's going for?
There is no sense in listing a card for rent, that never ends up getting rented. There are 813 of thos card currently available for rent. The goal, at least in the 'Ranking Market', is to keep the card rented out as much as possible... hopefully every day.
So let's take a little deeper look using the 'bid' button noted above, this is the screen we get:
zooming in:
At level 1, there is a recently filled bid at .300 DEC, and a number of open bids ranging from .110 to as high as .200.
This information gives you some insight into how the rental market is valuing this card at that time... and at that level.
If you put this card, Serpentine Solider, up for rent at .200 DEC, the bid system should pick it up, match it to that bid, and rent that card out fairly quickly.
Do keep in mind, that many transactions are being processed nearly simultaneously... so things can often change before you hit the 'submit' button.
Digging deeper at higher levels
You can dig deeper into each card level and see what bid's have been placed at those different levels too:
You can see above that there are no currently open bids for this card at level 2.
Take a look here at the higher levels:
level 3:
level 4:
level 5:
level 6:
level 7:
level 8:
Notice there are bids for this card at level: 1, 3, 4, 5, 6 and 8, but no bids at level 2, and none at level 7.
You will also notice that the 'market' for this card is pretty thin, not even filling up the top 5 bids, or the top 5 recently filled slots at any level.
What level is the strongest market?
The strongest markets here are clearly at level 4, and 8. With this information you can decide if there is a market for leveling up your card. Combining cards is serious business, and you can use this info to help make decisions on which cards to combine (level up). It also gives insights into new cards to buy, or even which cards you might want to sell or trade for other cards.
Sometimes selling a card, to buy a different one, that has more rental demand, might be a good idea.
Sometimes combining cards can make them easier to rent. But be careful, as you can see from the information above, sometimes a level 4 might easier to rent out than a level 7.
Different cards get different abilities at different levels, and there are limits to what cards you can play at what leagues... and with what level summoners. Those are important considerations in the Ranking Market and very much worth studying up on if you want to 'play the market' at your best.
Do consider the other main market too, the 'Power Market' before you go buying a selling though. That market is a lot more like vacation rentals than regular 'everyday' (or 'ranking') rentals. Maxed out common cards can provide a lot of 'budget' power and rent well using the CP metric.
Ranking rentals are focused more on playability and climbing through the leagues in the middle of the season rather than than just maintaining a league through the snapshot.
It can be more cost effective to rent early in the season, climb quickly, and earn extra daily quest chests, than trying to maintain a league level at the end of the season with super high rental costs.
Each card is it's own market
In the Ranking Market, each card is its own individual market, with multiple level markets inside each one. Say that three times fast!
Within those markets are even more markets, one for each splinter, edition, rarities, leauge, and of course gold foil and regular. There will likely be many more to come with land expansion.
That's a lot of markets, like a 'fractal marketplace'... very fitting for a game named SplinterLands ;).
Image by That richness of dimension is a brilliant design that makes both Splinterlands (the game and the markets), and PeakMonsters market tools, much much more than just the sum of their parts.
Hope you found this helpful, please let me know in the comments.