Problem: I want to save/invest, but can't do it by putting money aside or buying different currencies or virtual money, due to my spoiled character - whenever I need money I'll just cash the savings in one way or another. Even if I manage to gather some without spending, for some time, I might use it to buy something too soon and spend it all.
I noticed that due to this, for me it's better to buy physical assets because I won't be able to turn them back into cash, unless selling them, but that requires putting in work and is uncertain to bring back an equal amount of money quickly.
So I want to come up with some good ideas for physical things to buy that would be affordable (tens or hundreds (at max) of euros, not thousands) useful in daily life, and bring profit if sold in the future because of their value increasing with time. I'll give some examples of such assets below, some have more cons, others more pros. I'll list the better ones first.
Can you suggest more ideas for things that would serve the same purpose, and, preferably, outnumber the pros of the best ones I've already mentioned?
Seeds/sprouts of useful plants: does require some work to put in, but rather minimal, plants are aesthetically pleasing and (if they are practically useful) will give benefits with time. The quality of the seeds decreases with time, but if you sprout them, you can sell the seedlings or grown-up plants for more and also sell the goodies that the plant gives or use them yourself.
Car fuel: Car fuel prices now are constantly increasing. If you have a place where to store tanks with fuel, like a garage or a pantry, even buying small amounts of fuel can bring you benefits soon enough. You can either use it yourself for driving and save some money, cause in the future it will cost more, or sell it for a lower than the market, but higher than what you initially paid, price.
Art pieces, paintings, etc.: if you buy some art piece you love you can hang it on a wall, etc. and gain aesthetic value every day, then resell it in the future if desired, but it's tricky with the increase of the price if you buy rather cheap pieces of art their price is unlikely to increase, art pieces from famous artists usually cost a lot.
Gold and other precious metals, gems, etc.: useful only for aesthetic purposes, maybe more for women who would wear them daily, also wearing them daily and even keeping them at home you make an easy target for thieves, they also cost quite a lot even for small amounts, the price is also not certain to increase with time (or am I wrong here?), so seems like we have only cons here.
Antiques: I'm not a fan of antiques, when it comes to the described problem, because you need pretty much time, effort, and knowledge to turn them into profit.
PS: I'm not rejecting the possibility of buying virtual assets (except for cryptocurrencies for the reasons I initially described) that would bring value with time, just can't come up with any of those. Buying stocks is basically gambling.