To be able to give you an definitive Concept art that 'bites' one needs a professional artist and to be able to meet your desire a good dose of creativity. These two, I can humbly affirm I have sufficiently.
I have an excellent experience in Character Design/Creation, Concepts Arts and i will prove with samples whether it is cartoons or caricature creation or realism, I posses such skills, see my portfolio. I have worked in a graphics studio for 6 years till present and can cope with work pressure and tight schedules. In the event of any unforeseen circumstance or urgent work, I believe myself cable of remaining focused on the job and not bending under the weight.
With a steady internet connection here, and my personal laptop, I can guarantee a 98% steadiness in delivering my job effectively and on time within three days. I will sit up late at nights if the need be, mostly where our time zones are different or are not favorable.
I have put up a bid of GBP 100 (inclusive of freelancer commission) for the whole duration of 3 days. However as we work and make progress and modification, it might extend to a day or two, because whatever time is big, or is too little to be able to conveniently achieve this your wonderful project is what I'll put in.
I'll be glad if you will like to get back to me. Please reach me here.