Professional Classified Ads Software like OLX with Responsive frontend

PLEASE READ BEFORE BIDDING, AUTOMATIC BIDS WILL BE REJECTED. I am the owner of some free classified ad sites since 2004, but I have not been able to grow due to complications of commercial software that anybody can be found everywhere, some encrypted, some incomplete, others have become obsolete very quickly. I have worked with Esvon, Gold Classifieds, Xzero, Oxyclassifieds and others, I am currently trying OSClass Open Source, in my opinion very good to be free, better than many payment software. But really, I'm looking for an software that approximates to OLX, in my opinion, the best network of classified ads in the world , simple but powerful. Easy to place an ad in one step, load multiple images with pre visualization, easy to manage with or without user account, excellent location and search functions, featured ads, put ad at the top of the list, etc.. If you know what I mean, I need not to say what more is able to do OLX software, of course, there are other very good classifieds ad sites like Gumtree, kijiji, ebayclassifieds, etc.., Just to name a few, but nothing like the simplicity and effectiveness of OLX. If you are familiar with classified ad softwares you know what I mean. I am seeking a developer/designer who can make a software for classified ads from scratch like OLX but with Responsive frontend, or if you like you can take OSClass with its Responsive Bender theme and take it to another level. If you feel qualified for this task seriously and realistically, please make me a reasonable offer. I seek not pirate software or bad OLX copies, look for something that looks and works as OLX does, of course with a touch of originality but nothing too much elaborate. Please do not waste our time, if you offers is because you know what I want. By the way, maybe we can create a longterm relation ship. Many thanks.