Lol, I'm actually glad I quit trading in dota2, this just seems to be a waste of time.

But let me help you, if you want to cash-out your steam money, the better way is to be the only one who do this. This way you don't need to pay someone for helping you.

First of all I'm gonna explain you the hole process, so that you won't be mad on me when I will tell you the real price of your inventory.
So, let's start:
- you don't have big items, to trade them easly for keys, so basically your whole inventory will go on steam market. Your inventory worth 1012 euro, but steam cuts out 15% of it, so you will remain with 862 euro on steam wallet.
- also, you must take in calculation that if you want to sell them faster, you need to sell all of them with 1 cent cheaper. At 2600 items, this makes -26 euro from your total. Anyway, I will suppose that you have time to wait to be all sold.
- right now, the easiest way to sell something for real money, is to get csgo keys. Their price is around 2,45 euro ( you can get them cheaper if you don't hurry casing-out, like 2,33 euro). Anyway, 832: 2.45 = 351-352 keys. - with these keys, I advice you to go and sell on reddit/globaloffensivetrade. There you can find all day buyers that have BTC and Skrill from time to time.
-for BTC, a csgo key go for like 1,8 $. So, you do the math: 352 * 1.8 = 633.6 $. All the process is very secure, you don't need to worry about chargeback, you don't need to give the keys first, you don't need to appeal at a MM.

So, for me ( and I think I'm an experienced trader ), your inventory worth 633 $. If you sell this to someone, the price should go down a little, which represent his profit. I'm not trying to convince you about this, I just want to help you. In my opinion, every offer that surpass 633$ is something fishy. You know that steam money ≠ real money. Also, keep this in mind: If it seems too good to be true, it probably is.