Is it possible to keep creating adwords accounts and use some vouchers till the free credits expire? I tried this, my ads started showing OK, but as I created a second account (to another voucher), the ads stopped appearing.. Do you have any advice on this?
I believe that's called fraud. Google will catch up to you and ban you. Not a good long-term solution.
google will ban you if they see same landing page in two accounts also same ip range when you log in account.
And because they suffer from ethical syphilis. Most of these people will never learn how to make a profitable campaign. It's much more profitable to learn how to use the system instead of gaming it. If you learn how to use Adwords properly, your adspend will more than pay for itself.