Thank you for your detailed answer ACCTSeller. 
So what i read from you is that when i keep care that accounts i take into escrow are worth enough and the signature is matching and old enough and when i don't agree to followup loans that exceed the worth of the account then accounts should be relatively safe as collateral?
As long as you can get a specific signed message from an old enough address, and you are certain the account can be easily sold for more then the loan amount then the loan should be safe. You should however add an additional buffer from what you see as displayed prices and what you expect to sell accounts for as account sellers (as is the case for other types of items sold in the marketplace), to offer discounts and will often sell at below asking prices. So what i read from you is that when i keep care that accounts i take into escrow are worth enough and the signature is matching and old enough and when i don't agree to followup loans that exceed the worth of the account then accounts should be relatively safe as collateral?
The issue is that almost in every case (especially recently) that if an account is offered as collateral, the loan ends up not being paid.
You should also not take reputation points into consideration when deciding to make a loan (other then the fact that reputation point may increase the value of an account).
Yeah, the account being involved in a scam probable is a risk that can't be avoided easily.
If you were to buy an account via a [WTB] thread then you could take additional time to evaluate the account, or could have the seller agree to have payment withheld for a certain period of time (maybe a few days) in order to wait for any scam accusations to come to light. When making a loan, there is a bit of pressure to get the money to the borrower quickly. Maybe... if someone really accepts accounts as colletaral, the account should be considerably more worth than the loan. Maybe 150%? That way it should be avoidable that the account owner is trying to sell through that way. It would not be worth it. But for a normal person wanting a loan, it would be ok.
It really depends on how good of a salesmen the borrower is. If they are not a good salesmen then they may be willing to accept lower prices/loan amounts then what a good salesmen could sell it for (also note that people have complained to me that I was offering to low of an amount to buy their account when they were asking for a loan with their account as collateral). I doubt that trading accounts is very rewarding nowadays. It looks like the prices for accounts are dropping constantly. Maybe an oversupply of accounts now. So i don't think that i will trade accounts. Selling them should be the exception i think.
I don't think it is very financially rewarding, although you could likely buy them at low prices and then sell them at high prices if you have both a [WTB] and [WTS] threads because of the fact that account selling is somewhat taboo, so pricing will almost always work in your favor (significantly) when others come to you. Prices are declining at a rapid rate, and there appears to be oversupply in the market right now, so you could be stuck with excess inventory that eventually becomes worth less then what you paid for them. From what I have seen, the lender having to sell accounts they took as collateral is more the rule then the exception.
I wonder if people would give altcoins as collateral since it nowadays is pretty easy to exchange them to any coin they want...
Some people may own a particular altcoin because they believe it's value will rise in the near future. If they need money then they could offer that altcoin as collateral, then be able to spend the money they need to spend, then repay the loan to get the altcoin back, which hopefully will have increased in value since then. Thanks again for your detailed answer!
I think i would take my time to evaluate an account. When the loaner would pressure me then i would tell him to go away. I had to learn that fast decisions are pretty much always wrong decisions. Not with accounts but with trading and investments.
> (also note that people have complained to me that I was offering to low of an amount to buy their account when they were asking for a loan with their account as collateral)
That's funny.
Might be that some see it as a quick way to sell their account. And honestly, when i see the loans that some are giving out for certain accounts then i'm pretty sure it might be the better way to sell an account. For some reason some borrower loan out way more than an account is worth. Maybe old prices or this valuation bot that was said is showing too high value?Not to forget that the new forum might come soon. When it comes there is a chance that the old forum accounts will not be worth anything anymore.
So they hedge against you with loaning out altcoins? Hm... guess the loaning rate needs to be high enough to average that out.
I wonder if i should try it. I mean i already know something about account worth. And as an escrow i had to learn how scammers might think. When i think about getting 10% a week then this does not sound bad for me. At least as long as the scam rate is not so high at the end.