Buy a used car from a place that does financing. Be prepared to also have to pay your insurance in full, btw. You don't want to go to one of the big deal places with brand new cars, just the smaller ones that you deal with directly. Interest will be high, so unless you want to pay cash in full, be prepared for that as well. If you can make the deal, you will have something to use for a credit history. It may not be worth as much as you imagine, that kind of credit history, but it will be more than you have right now.
There are some places in Surrey near the Scott road station that I have been to that do this, and even if all you end up doing is a 3 to 4 payment plan, as you say you give them 30-50% deposit, then finance the rest over 3-6 months, and you are driving same day.
I suggest you avoid doing any deals with or using clients or other sps to help out. Be 100% responsible for yourself, do it for and by yourself. If you need someone to help you find a good reliable vehicle, you need to be able to take it to a mechanic to check it before buying. That would be something you can find a friend to help with, and if you have no suitable friends, possibly ask a knowledgeable client for advice. (this doesn't contradict what I said earlier--basically avoid any and all financial dealings thru a 3rd party, it will only lead to trouble)
oh, and anyone will tell you that it will be very helpful for your future to have 2-3 concurrent tax returns to provide when attempting to get financing for things.