You can input crafting stations either tradeable stations or non tradeable once you use them which are the attunables for each set in game. Also you can use your merchant/banker as an npc in house but it counts towards the npc limit as well which sucks.

The guild hall you refer to is a shared player home. ESO does not yet support guild halls. Large homes do make great guild halls tho as there is plenty of room for services.

Services that your home can have are crafting stations, a banker, a fence, & a merchant. For crafting stations you can have the typical woodworking/blacksmithing/clothing/dye/enchanting/alchemy/cooking fire/transmute station. You can even do attunable stations for woodworking/blacksmithing/clothing. Meaning your stations can do set items. The merchant does not repair and the banker cannot access guild banks/stores. And the fence has a service fee for using. These limitations are to encourage you to use the resources in the world since it is an mmo.

I've had great fun personalizing homes. Once I pick a theme for my house, I enjoy finding furnishings to compliment that theme. My primary residence has all 700 slots filled with furnishings. And, once ZOS ups the item limit, I have plans for the future.

It's a huge gold sink, both buying the houses and the furnishings (or plans to make awesome stuff). I have easily spent over 5mil on my Hundings Palatial Hall (including purchase price)..but I absolutely love it XD. I also have about 500 furnishings stored in other homes.... and I'm getting ready to buy another small home to decorate. Is it super useful? Nah. I mean I have all basic crafting stations and a transmute station, but I don't even go to my house every day. I do enjoy decorating though and I always love talking with fellow housing players. Probably the most useful houses... two of the guilds I'm in have houses with every attunable set. That makes doing master writs sooooooo much easier. The one guild in particular, has the Gardner House in Wayrest. Top floor is all woodworking stations, ground floor all clothing stations and basement is all blacksmithing stations. All of them are in alphabetical order making finding each set a breeze. Plus they also purchased all 12 mundus stones. Talk about a one stop shop.

My wife and I have the Mournoth Keep, because there's a wayshrine, and a dolmen, just outside the front door. We never have to waste gold on fast travel, it takes just a few more seconds to free-travel home, then run outside to the wayshrine. The dolmen is an added bonus, as it's pretty much always active, so a great source of quick and easy XP+loot.

Aside from that, we have our blacksmithing, clothier, woodworking, enchanting, alchemy, & dye stations...as well as a shared banker and merchant...so we can avoid the craziness of the cities, other than when we need to run to the Rawl'kha OR and Stable.

If you have the Banker the house works as a great inventory management way-station for those pesky, "who has what now?" moments with your Alts... this is especially helpful if, like Me, you find the town banks annoying.

Home crafting is good if you are into doing the writs!
Its convenient & a fun little RP Moment, BUT! ...its a commitment to do the master writs necessary to get the stations.
& you can make your personal use potions and foods & glyphs there... but set bonus equipment is a whole other barrel of banekin.

I think for a lot of Us the decorating & hanging out there got us hooked and the practical stuff is bonus.
I'm almost embarrassed to admit how much I enjoy sitting on my porch while its raining!
My ESO Life.

If you're going to stay in a guild with all the crafting attunables and with a target dummy and aren't interested in the personalization and design aspect? Sell your writs. No point in investing time into something you're not going to have fun with.