Comission from Publishers - Help Required Please :-)

Hi Guys, Happy New Year :-) I wonder if any of you could offer some advice and assistance please ? I have a small collection of mixed media work which i am thinking of submitting to a number of publishers : 1. Whitewall Galleries / de Montfort Fine Art 2. Washington Green / Castle Galleries 3. Artko 4. Buckingham Fine Art It is a style i have been perfecting during college, and for the last few years. I draw inspiration from a number of artists, but i believe my style is my own. Without wanting to be taken advantage of, i am thinking of approaching the 4 publishers above, with the view to selling my originals and also rights to re-produce my work as prints or editions. I have had 8 months working on my art since being furloughed due to Covid19. During this time, i believe i have honed my skill, and have a style and a number of designs that are quite unique. I have never approached publishers before, and i dont want to taken advantage of, or seem wet behind the ears ! I also want to be realistic in what i could achieve in terms of commission etc ? I'd really love some insight in the type of commission i could hope to achieve by a publisher such as those above, who would produce my work. I want to be realistic, not appear greedy, but i would also want an idea of what my position would be as an independent artist, and how much commission i could expect from a publisher, and if there would be any guaranteed payment ? or up-front payment ? Apologies for babbling :-) I just want to prepare my portfolio to submit Thanks in advance, for anyone who can shed some light on what i might expect, and anything to look out for, or be careful of, in advance of laying my stall out in front of publishers Look forward to hearing back thanks Leyla x