Its been suggested a few times to be able to sell items for bits in like an NPC store kind of way. 

I havent ever had millions like others but never had trouble having bits either. Sometimes when people start out they end up with more horses than necessary and the beginning and expanding a lot and it can definitely hurt. While that isnt always the case, starting with a small stock and building up to better horses can help. I see a lot of people with large amounts of low quality horses they are trying to sell. Again, not always the case but I think that does hit a lot of people. 

As I have said in other posts though, I do agree it would be beneficial to have a NPC store to sell items at a set price as I often have way too much of stuff and when they are a dime a dozen its hard to sell to other players. I even have been having trouble with gems lately and I usually sell those at lower prices than most. They are just so easy to get. 

It does really pay back, if you have a small number of horses that are high PS and nearing (or even in) Tier 2 disciplines. It can actually carry your entire stable.

To make it a bit easier for those that are struggling, I have a 5-gem trading hub in the trades -->look under the Looking For tab<-- There have been people taking advantage of it, which is great.

I also have a forum that I offer at-cost, high-quality horses that are discipline horses. Iberians and Araloosas.

But earning money on here does take some time. As far as my experience has been, we don't [or I haven't] made any significant money selling horses at all. Almost all of my money (somewhere in the 95 to 98 percentile) has been solely from disciplines and from halters. And these is all from my own horses that I've developed into quality 4- and 5-star stock (halter shows) and the disciplines really only need you to develop a line of competitors. My iberians, as excellent discipline stock as they are, are rather ugly in their star-values... I think the highest star value I have is 3-star. But they're killing in disciplines.

So, instead of trying to make money selling horses, choose one line and start developing it. Takes about three to four generations, but consistent leveling and training will get them into the discipline area they need to be. As far as halter is concerned... as long as a horse is 4 or 5 star, they can generally earn bits with just that.

I do have to put in here however, a well-leveled horse could be worth quite a bit more when up for sale. With two basic rules... many of us that are looking for well-leveled horses will also be looking for foal production and either good stars OR good PS (usually one OR the other can be forgiven). This means, that if you're looking to level a horse, you should consider restricting or not even using the horse as a breeder and to never miss a training session.

If need be as well, you can freeze your tabs and focus on your horses that do better in competitions and run through the Dark Horse Mine. 

Myself actually, I had got down there in bits. I froze all my tabs, except Chincoteagues, and worked on them while running through the mines. I believe the new gems, Rose Quartz, Onyx, Amethyst and Citrine still sell decently enough to get some bits. Then once I began doing better, I opened up my Thoroughbreds tab and really began raking in the bits since I have worked on my line and bought horses/bred etc. I believe some folks might still want some of the summer dyes we just had so try tossing them into the Marketplace for a set price, for example 1k per dye and you have 10 of them? Put them up for 10k flat and can usually be sold off.

If you're looking to pay money to get bits, then buy ingots and sell them on the marketplace.  You can make small sales of 50 ingots for 25k and they'll go fast, and you can even press the price up a bit and they'll probably still sell, just after more time.

Outside of that, halter shows with my huge percentage of foundations still nets me a lot of profit each day, though it varies.  I was making an easy 50-75k per day with straight halter shows on ~200 horses.  It costs more to enter, but if you have a horse that really places well it can make a lot of money.   I just put most of them in at least a couple shows, and even if some do badly I still get a net profit.  Careers can also make money without paying any of the fees.

Some wild horses sell really well and I suggest with any 1* horses to put them in 2-3 halter shows so they gain a good number of points still and then use the rest of their energy to explore in hoofbeat plains.  I've had two Chincos that sold at 1000 ingots and 700 ingots respectively, and most skewed/dun/variation/overall good looking wilds sell for at least some sort of profit.  Don't use the treats to get them because those can also sell for very high amounts, but just wait until you can get lucky through use of lassos/whistles.  You'll see a lot run, and it'll break your heart sometimes, but then you get that secret flaxen carrier Chinco and you're set.

Then there are other ways of making money.  Selling extra items, creating art for people, etc.  The stud fees from my 4-5* horses aren't enough to keep everything running, but they are a nice bonus.  And they're just foundation/wilds, but still get a steady number of uses (at least in my opinion).   I don't make much money selling horses, despite selling one every day or every other day.  They just don't sell quickly (and some not at all) because everyone is always pushing the limits of their stable, so they want to buy the best bang for their buck.

I've been down to 5k before from pulling foundations/buying auctions and not paying enough attention though.  I just spend what's left on putting my horses into halters, max out careers on the rest, and come back in the morning to more money than I had the night before.