First I am going to weigh in on the idea of buying vessels. ... Any shop that claims to be selling vessels containing spirits is by default fraudulent. And yes, scammers will commit all kinds of work and time to create a good hook to make money from. The beneift to them lies in time. spend a hundred dollars for a professional looking website, create a product that is believable-enough to let new people fall in and yet leave older people simply shaking their heads instead of actively opposing it, and then you can sell these 'spirits in a jar' or other items for years and years. And to protect them legally all they have to do is compare them to the marketing of a pet rock, and maybe put a small tag line somewhere on their site or EULA stating 'for entertainment only'. Also, the added protection lies in their lesser value. a person is much less likely to go to court over losing $20.00 than they are about losing a hundred or thousand.
As far as why it is fraudulent, first off, glass (or ceramic or clay or metal or whatever) will not contain a spirit in any way. They are intangible energy that operates on a wavelength outside of physical boundaries. And placing wards, runes, or other bindings and imprisoning a spirit within would quickly lose power once the jar has changed hands, as the fuel behind that magic would also change hands. Not to mention in the off chance a jar -was- genuine and sucessfully held a spirit, it wouldn't exactly be happy about it. I know I wouldn't appreciate being locked in a box and then sold to someone else.
That said, if a place is selling -prepared- vessels that are able to be used for such a purpose (but not containing a spirit) may be a bit more legitimate as one can certainly do the prep work and then send off an empty vessel for someone else to then use as a tool in their own summoning.
The benefits of calling for a spirit yourself are incredibly more worthwhile. First, you learn a new form of magic and symbolism. Second, you can call a spirit amenable to actually being there. Third, you can be sure you are setting the appropriate ground rules for the relationship. Fourth, you can be specific in your intent for the summoning, and so also specific in what you gain.
As for your concerns about accidentally calling an 'evil' or malicious entity, ... look at it this way. When calling for a spirit it is like cracking open a phone book and making a call. if you just pick a number at random, it is indeed a big pile of maybe as far as what you will get. it might be someone nice on the other end, or it might be a mischievous prankster, or a sympathetic granny, or an angry religious zealot, or a psychopath. but if you look through the numbers and businesses you can find a number for specifically what you want, and have some knowledge of who you are contacting. So if you are looking for a plumber, you will look for and call a plumber, not the pizza guy.
The trick lies in being specific, and self-reflective. When performing a calling, keep in mind the intent of your magic. What are you looking for? What are you hoping to learn about? Are you looking for a guide or a simple companion or a protector or... something else? Make your calling specific, and tailor the working and actions of your magic around that.
don't just ask for a spirit. Ask for an entity of light that will help you to grow as a person towards your spiritual goals. or ask for a guide to make itself known to help you overcome a personal challenge. or call for a friendly spirit to come and enjoy your company as a companion in your learning and upliftment. And declare that no entity with intent of harm may be within your presence. It is all in your intent, and the wording you use to express it.
Maintaining a positive energy around yourself and within your home also goes a long ways in preventing subversive or harmful entities from coming as well. The positive energies literally push out darker or lower vibration ones.
Are your spirits ones that you have gone through a shop to communicate with, or did you summon them yourself? As for plants, I have 10 in my room alone haha ! My plant family has been growing lately though :-)
Honestly, you probably have at least ten spirits right under your nose that you've already worked with on some small level. Your plants have their own spirits, and depending on their species and how well you've taken care of the physical plants, they would likely be willing to communicate with you and help you out in return for your care. No need to conjure up some unfamiliar entity, especially if you are new to spirit work.
Just like Spirit75 has mentioned, these vessels are a scam. They cannot bind spirits into objects. Many entities who are claimed to be bound there are Demons, like Djinns, Faeries etc. It is very, very hard to bind a Demons into an object and they wouldn't take it nicely.
I've searched up Djinns on creepy hallows and they just claim what I ternt claims; something which is not accurate about them. It shows first of all they are lying, because they haven't communicated with them or have searched about them and have no idea about them at all. They even reffer to them as "it".
Things are more complicated and any type of spirit you tried to bind would just make them hostile torwards you and/or away from you; you would not establish a possitive and friendly relationship with a spirit like that.
You Can summon spirits on your own, and you Can have spirit friends. I advise you to do that because-except the fact you'd waste money for nothing-the Magick of summoning otherwordly creatures is just Amazing, Extremely Charming. And I promise, they would appreciate more if you showed the bravery to summon them on your own and use offerings dedicatd to them, than trying to bind them on your own.
About the entities which will want to harm you; again, Spirit75 is correct. If you call upon anything you are in a huge danger, especially if you have no protection. If you say something like "Is anyone here?" you open the space up to all the entities and anything can come through. This is called as "Informal summoning".
"Formal summoning" on the other hand is the summoning in which you call upon something specific; when you call upon that specific entity no one else is able of hearing the summon. However, when you call upon a specific entity if that entity doesn't show up another one can take their place and answer; but; if you have protection then no problem is going to arrive. The possibilities the Universe has given us are limitless...
You can surely search for spirits that have friendly intentions or intention to help and aid you in your spiritual path. Or even for both. :) I don't know from Fairy things, but if you want to start with a friendly entity that's the "perfect one" for beginners I Definitely, Definitely recommend Paimon. You could send me a message in case you want to know how you can in contact with Paimon. I would love to help you.
About the Faeries..you could start with offerings, milk, honey... You can search for them or some specific of them and after you know enough you could try and summon one, with protection of course.
I have alot of experience with Spirits, especially Nature Spirits and Faeries. Ive met alot of Faeries (whom are still great friends of mine). They come and go as they please usually. Pixies, Sprites, Nymphs and Dryads are quite friendly usually (though Dryads can be very quite and Nymphs very tricky). I woukd recommend a comfortable space for them to stay, put some milk and honey out on a saucer, or anything! Cream, sugar, nuts, berries etc. They wont physically eat it, but they will eat the energy from it. .
I have read about keeping spirits in vessels and I always found it a little puzzling. I have communicated with spirits since I was a child. My familiar is a spirit. I have never had to "keep" any of them. They come and go as they please. It is my belief that they will return to you if they want to work with you. I, personally, do not want to force a spirit to be involved with me if they don't want to be. My concern with purchasing a spirit is that you wouldn't know if they had volunteered or were forced to be bonded to that vessel or if they would want to partner with you.