How to get skins with low investment

Using the following pages:

https://hellcase.com/
with the promo code:
7905327
Deposit 5$ on skins or money then you will able to use the "daily free" feature that allows you to claim money(or skins) that you can use to buy cases that gives you skin.

https://csgetto.com/
without promocode.
Just add CSGETTO to your steam account and you will able to claim a case every day.

https://csgoempire.com/
with the promo code:
Cobollatin
You will be able to claim 0.01 coins every 6/8 hours that you can use to change for skins, with a low deposit requirement to withdraw.

Buying with bitcoins:

You can make bitcoins easly and use them to buy skins at steam. Here is a short list of faucets that you can use:

https://freebitco.in/
You will able to claim bitcoins and rewards points every hour, use the reward points to redeem bonus.

https://upbitcoin.com/
You will able to claim bitcoins every 20 min.