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Are you offering any kind of collateral for this "investment" or is it based entirely on trust? If on trust, then why should anyone trust you?
It is based on trust and a valid registered company at the Dutch chamber of Commerce (and a contract).
I've done trades in BTC for a total near 300k in the past on this forum. Some shows in my trust rating, and hopefully their are also people here on the fprum that can bouch for my previous webshop (usbminers.nl ) that was one of the biggest webshops in Holland for the mining community. Their are forum members here that have ordered for over 50k at my store in the past.
Your trust shows that you have only been entrusted with a few hundred to a few thousand dollars worth of others' money at a time, and for short periods. Your trust also shows something closer to around $10k in trades as opposed to $300k, although some of your trades may not have involved the leaving of trust rating at their conclusion.
Could you maybe have some of your trading partners post that they have traded with you, the value of the trade at the time of the trade, and if they trusted you as part of the trade? Another concern is that most of your trades involve Casascius coins, which is Suspect is not the case for your business proposal (I don't know what you are doing, so I might be wrong on this). How much experience do you have in the line of business you are proposing entering into? Even if you are not going to outright steal the money, this does not mean your project will automatically be successful.
Getting people to sign my trust will be hard due to privacy/anonimity, but what I can do, I can still sign/transfer from the following addresses:
https://blockchain.info/address/1DzCnrgNS3MACNU5uAZ37AKA4nTV27yk5F Total receivement of 232BTC
Verifyhttps://blockchain.info/address/1Hagmi63eqvw8HDfPbVNag4s3mAFMEpmAq Total receivement of 264BTC
Verifyhttps://blockchain.info/address/14zDigY726eMK3RnnvrLCE9TJiP5htkHEz Total receivement of 5.44BTC
https://blockchain.info/address/1GBUT6vqgz5aMMYRR6FCU7ktFx9Ykz2QUy Total receivement of 9.81BTC
https://blockchain.info/address/16pb2twBPg6CEMbKZfq92oPZQqgdTW2dFo Total receivemnet of 47.60BTC
Totalling 558.85BTC of received funds, although there will be duplicate transactions from one address to the other, it also shows a total of $218.500 worth of transactions from me to PCFli (
https://bitcointalk.org/index.php?action=profile;u=253683), he can confirm that I have bought big quantities of miners from him, and he has also trusted me in the past with big payments only after receiving miners. Hopefully this will boost the trust a little into me managing bigger amounts of BTC.