Transplanting/ final soil question

Whats good,, I have 4 plants growing in the woods that are now 23 days old and doing excellent. I am going to be transplanting them in a little while and was just curious of two things. I have heard 5 gallon pots are excellent for a final plant but as I am young and don't have a ton of money, i was just wondering if you could go any smaller than that for your final pot..Additionally, i was wondering what a good final soil mix would be to use for my plants from a store like lowes or home depot? Would some regular potting soil and some perlite be a fine combination?

This is also a pic of one of my plants from a few days ago so u guys can see where im at

I would go with kellogg's outdoor patio plus for soil, it's the exact samething as FF ocean forest. Also while your there at Home depot or lowes pick up a 5 gal bucket for like $2 and that should do you good. If you go smaller, you will get smaller yields, spend the few bucks and you will be very happy you did.