A few questions.

I've arrived pretty late to the RPG maker party.

There's been a story rattling around inside my head for close to two years and now that I have some time, I decided it was time to see about making something out of it. I picked up MV because it's supposed to be, at least technically, superior to all the other versions of the program. Unfortunately, I've found it isn't exactly a wellspring of resources. It seems every time I find some neat tilesets or some sprites that look perfect, they're for one of the other versions of RPG Maker.

I picked up a couple of DLC's from steam and, I'll be frank, they weren't worth the asking price. I'm not likely to go that route ever again.

So, I suppose the first question would be: where do people find decent resources, for pay or for free?

I've found some interesting bits here (this website) and there (some others), but finding things for the creation of world maps, such as towns and other places of interest, is a lot harder than I expected it to be. There is a lot of technical stuff, like plug-ins, which is very cool, but I find myself really having a hard time finding the same level of basic content that's available for older versions of the program.

Are there any particularly good (and reliable) artists who do requests or commissions?

I'd be interested in links!

If so, what's the general going rate for, say, a set of tiles?

When asking a couple of people I know who made their own game, they more or less said 'way too expensive, use free stuff, it's usually better anyway'. That said, I'm still curious hear about peoples own experiences with buying, commissioning or requesting assets.

How in-depth do people who produce free assets expect credit to go?

I'm assuming a thanks, of course, but it's left open to a lot of interpretation. Is their name and a link in a text file, included with the game sufficient? Do I need to fine-tooth every tile used, reference it in the credits, in-game?

The vagueness of it makes me hesitant to use assets I've found in case someone comes along, feels I didn't give them enough credit, or dislike something about my project (which is common, since most of my stuff includes adult and non-binary content), and demand I remove all of their stuff from a more or less released game. It doesn't help that many people who posted content don't seem to be active anymore, or at least haven't been posting for some time.

I've seen some epic projects in other modding communities burned down because an artist is cool with someone using their stuff, then changed their mind or tries to leverage it for something they want. One sticks out in my mind, where a very talented artist released some content on Nexus for general use, only to come around later and start expecting people to include furry content in their projects if they wanted to keep using it -- and crying foul when people told her no, on both issues.

I really, really, really do not want to have to deal with that kind of thing, so knowing the general 'standard of credit' going forward would be nice.

I guess that's about it. That sure was a lot of words, wasn't it?

Have you looked in the Resources section of this site? There are vast quantities of resources of all descriptions there, certainly more than enough to make a decent game.

Credit is usually just the inclusion of the artist's name, though some specify that you also have to include a link to their website. This can either be by credits in-game (e.g. scrolling credits at the end) and/or a txt file included in the game's folder. All resources posted here have their terms set out clearly. I don't know how 'adult' your adult game will be, but note, some terms do include restrictions about their use with pornography. You will be able to tell this from the terms as set out.

A set of tiles, made just for you, will cost in excess of $10,000. It is a hugely time consuming task. It is for that reason that people buy the Resource Packs if they can't find what they want for free. Celianna's Ancient Dungeon base pack and extensions (Jungle, Winter) come to mind as good quality packs. As yet there isn't the range of assets for MV as there is for VX Ace and XP, simply because they have been around a lot longer. Learning to use e.g. GIMP (which is free and basically does all that PhotoShop does) to futher edit tiles to customise them will extend the range of tiles available to you.

I have only commissioned sprites, not tiles. Once you have access to the Classified section of the forum, you can browse the threads there to see what's on offer and at what sort of price.

The DLC on steam are actually cheap (especially if you get them on one of the sales or from a steam-reseller) based on the mass of the content and the workload that went into them - but of course if you can only use a few tiles each that might not be worth the purchase.

There is a forum area for paid commissions here, but to protect people on both sides they need to be a member of the community with more than 30 posts to even see that area. If you checked there, you would see that prizes for exclusive tiles are around 5$ for a single MV-sized tile.

That is because it takes time to make a tile, the artists who create packs are usually working several months for each pack. And if that work is exclusive, the person who commissions them has to pay those several months of income.
Non-exclusive packs like the ones sold in shops are cheaper because they are sold to hundreds of people - but even then the money gained has to reach those six-digit-figures to pay for food, which is why you won't see large packs cheaper than about 30$ even on steam.

As for changing of artist opinions on terms-of-use, that is why we ask everyone posting resources here to post their terms. And while the artist can change those terms if he wishes (and some did so, for example there is an entire series of Ace-battlers that was pulled off the internet by the main artist, resulting in the scripts for their use becoming useless), those changes can't be done retroactive. Which means that if you used resources under specific terms, those terms will continue to apply (but the new terms will be correct for newer resources done after the terms changed).

That is also another advantage of shop purchases - you get an EULA with them and that will remain in effect even if the shop changes the EULA for later purchases.