@Natelinchen The ability to hire a butler comes with the Vintage Glamour Stuff Pack. I personally love having a butler if my Sims can afford it... or if they have the free services perk. Butlers don't cover everything. and some have better personalities than others, but they are a fantastic safety net, and I have had many great experiences with them. I had one in the home where I had a servo and that broke down continually... and the butler would autonomously fix him, I have one in my home with infants where he is a better assistance for a safety net tan the nanny I tried (though not 100%)... the butler I had that was a lifesaver was in my most chaotic home where I had 6 sims, a servo, and a dog, and several were attending university, 3 roommates... and one of the sims was a toddler in the middle of a needs-depletion bug... That butler helped with everything from cleaning, gardening, servo and other repair, social interaction, toddler & pet companionship and some attendance, to keeping the roommates happy and cared for. No standing around in that home! 😉
You can check your butler's personality, and even adjust his traits if you don't like them via cheats (if he/she isn't a good fit to your household)... or fire him and hire a different one. That pack comes with the smallest and least expensive bar, also (a globe), and my favorite female up-do hair. Butlers could use some tweaks to their code and are not perfect (my current one seems obsessed with the tub and takes a bath at least once a day... unusual for a butler, they seem to have slow need decay... but in the end I gave up worrying about that and I put in a second tub - hahaha!) but I'm fine with 'working within that' and am a fan of them. As far as adding a bed for them, I've done everything from give them a nice little mini-apartment room within a huge home (which was rather a waste - all they do is sleep in the bed occasionally - but could be used via locks to encourage them to use their own bathroom, etc... though then you would need someone else to clean the other bathrooms if they can't get in) to assign them to a bunk in the kids' room. There is some good intro info on them at this link: https://www.carls-sims-4-guide.com/stuffpacks/vintageglamour/butler.php
@Natelinchen ... I forgot to mention sprinklers. Seasons comes with a sprinkler, and it can be invaluable with a huge garden. It is useless, though, if you don't upgrade it to 'unbreakable' and 'no puddles'. In that case, they still break occasionally and need to be fixed or replaced, but they are a huge help.