Make a 2 out of 3 multisig. One key to the buyer, one key to the seller, one key to the escrow.
As long as everything goes fine, the escrow doesn't really have to do anything, so he doesn't get paid. He only gets paid if there is an dispute and he has to actually do something.
I think, OpenBazar is using something like that and it makes sense.
This kind of protection is much better than chargebacks since, buyer and seller are protected. I don't get this whole "Buyer is always right" policy, from most payment processors. Buyer are also often fraudsters and make a lot of damage to merchants.

Inflation is a pretty inaccurate thing. It makes sense, when it comes to food, shelter, etc., but it doesn't make much sense, when it comes to technical stuff. Look at the cost of a computer 20 years ago and now.
The service sector is also just way bigger than 20 years ago. That means, that when you start a business, it might be sufficient, when you can code to have product, you can rent the whole infrastructure pretty cheap.
But that also means that there is much more competition. Lower costs=more people try to get into this market.
So, I don't think, you can't really compare internet in 1980 with Bitcoin today. There are just so much things, to take into account.

as long as there is no split, you are fine. I am not sure, if the mining pools took countermeasures to avoid a split, but there wasn't one for a while now.
There are also more nodes which have updated their software, so that makes the network also more secure.
As far as I know, there wasn't even any damage done during the splits.

This whole thread is a good example, why so many people keep away from Bitcoin(and why, in my opinion a lot of people shouldn't have kids)
I most certainly would restrain from using words like "blockchain" or "double spend" when I tell a person (kids are just person, who haven't had as much experience(which is a good think in a lot of cases), they are not stupid). I would restrain from telling them about volatility.
So, I would explain it, the same way, I explained it to my sister(who is 22 now).
Download this app on your smartphone, write down this words for a backup, keep the backup save, here have some Bitcoin, look there is this site, where you can use your Bitcoin.
For a person, who depends on you(aka kids) just give them Bitcoin from time to time to use it(aka allowance)
For a person, who earn their own money(aka adults) show them a good exchange to convert fiat to Bitcoin. Now you can warn them about volatility, not putting all eggs in one basket and so on.
If they have questions, try to answer that questions in a simple way(and here is the big advantage about kids over adults: they ask more questions and they tell you, if they didn't understand the answer).
So, keep it simple, get your priorities right(most important thing is, how to use it, not that it will destroy all banks)

That still doesn't make sense. From the way, I understand Bitcoin Core, it creates 100 addresses at once.
So, I used address 1-10 and than made a backup. The backup contains all 100 addresses. Then I used address 11-20 and came to mind, that I should encrypt the whole thing. According to you, it deleted address 21-100 and creates new addresses. It still has address 1-20 which could contain money and which are in the backup. I could even have given out one of these addresses for let's say weekly payments of a sig campaign here on the forum and would get Bitcoin in the future.
Only money that is send to new addresses is save.

So, I am still right about, deleting your old backups after encrypting your wallet.

Keep in mind that Bitcoin is the most used decentralized digital currency: more value, more transactions, more people who could gain from attacking it.

I could also just write my own website from scratch, nobody cares about and after a year proclaim, that I am the best programmer in the world, since nobody hacked my site.

I guess not everybody would have to store such transactions, if there is a bureau that wants this data, they can store it them self.
I also don't see the concern about tempered records. You can't make a fake "address A tried to send money to address B"-transaction, since it still would have to be signed with the private key of address A.

OK, thanks, that makes sense.
But what if, there is no C or C is just too small to give a good additional fee? Is there a workaround for that?

Which exchange is cheaper than kraken?
Which exchange doesn't take bank transfers?

I really wouldn't recommend faucets.
I also wouldn't recommend localbitcoin. It might be nice to use at first, but it get's annoying if you do it several times, so the time that you initially spend to register an account on an exchange pays off pretty fast, not even speaking about the involved fees/higher prices.

What's done is done.
My BTC are currently worth less than when I have bought them. A lot of people would argue, that I have lost money. No, I didn't, since I wasn't stupid enough to sell them at a lower price, than I bought them.

I also mostly just buy new coins, when I used them, so there is also no loss there.

People are just worrying too much. The only loss is in your head(pun intended)

When I get this right, you still have to register on the website to use this app.
The 2k fee still doesn't make sense.
This is how fees work:
https://www.kraken.com/help/fees

you have to pay a fee of 0.35% for the first 5k USD you spend. That doesn't mean you have to spend 5k. It just means that after you reached 5k you have to pay less fees.

If that would be true, than every real life transaction would seriously be broken. Even if I attach a ridiculous high fee to a transaction, it could still take an hour to confirm, since it could take an hour to find a block.

What exactly do you mean by sending node? Do you mean, when I shut down my client the transcation could be lost?
When I use mycelium, I just activate my internet connection for sending the transaction and deactivate it immediately after that, but I still had transaction that where unconfirmed for some hours and got confirmed in the end.

Could you explain, what exactly you mean by this sentence?
The only bitcoin-related kraken, I know, is https://www.kraken.com/
Nothing to download there and no fee for just registering.

So, adding a passphrase creates new address and send all funds from previously created addresses to the new addresses?

That didn't answer my question, or maybe I just didn't understand it.

So, let's say we have address A (1BTC) which sends to address B(merchant: 0.7 BTC) and address C(change 0.2BTC) so it's 0.1 BTC fee.
So, can I change receiving address B? Or can I just say, there is less going to C, so the fee gets higher, but then I also could say there is less going to B, so the merchant gets less money.

That is exactly my problem. If you give every random guy you met over localbitcoins a copy of my ID, you can be sure, someone will use it for identity theft.
I am even worried, about the copies I gave to MtGox, even thought it seemed serious at that time.

When you delete a transaction from your wallet, doesn't mean the other nodes will delete it. Right?
Does Replace-By-Fee mean that you can replace the output-address? If so, then this "feature" just seriously breaks Bitcoin.

The only premature thing, was to delete his first post.
There is nothing wrong with posting a theory. The whole point about posting a theory is so people can look into it and tell if the author has made some errors.
Nothing to be ashamed of.

What do you want to tell us with this screenshot? It doesn't sync?
Are you aware that you should be able do use your local blockchain from your Bitcoin Core-client and you should also be able to connect to Bitcoin Core-nodes?

Which client can "override" a transaction aka double spend it?
How do they trick the nodes, that just won't accept a double spend in their mempool?