Create Wordpress Plugin

I need to create a Wordpress plugin. This will be done in 2 separate stages. The Front End and The Back End. I am requesting the quote here only for the Front End. Whoever gets awarded for the Front End, will also be offered the Back End, unless I am dissatisfied with their job on the Front End. The reason for only doing the Front End first is for expediency to get the Front-End unified as soon as possible. And it will probably take a lot less effort to complete. Only very experienced developers will be considered suitable for this job, who can demonstrate competency at completing what is being asked here. This job requires to setup WP to use 2 separate Databases. The WP Database and The Plugin Database. The Plugin Database must be Admin definable as to it's location. The Admin will add The Database Username and Password into WP. The Database will not necessarily be on the same domain as the website. The Plugin Database is essentially the current Domain Database. I don't want any suggestions about combining these 2 databases. I have setup the WP already. The website which I am converting to WP and the WP website both currently exist and are working in Parallel. WP is using the Colorlib Shapely Theme. I chose this theme because it is a Flat Bootstrap Responsive Theme, and because it is a basic theme without any bells and whistles. It should suite the job well. The old website is [login to view URL] I need to recreate the functions on that page into WP pages. The new WP website is at [login to view URL] So I need the searchbox to be converted into a WP page, centered in the middle of the page. After a search is completed, I need that when a visitor clicks on a Buy Now or a Make Offer Link, they are sent to new separate WP Buy Now or Make Offer Contact Pages. But only after checking first if the visitor is first logged in. If not logged in they will be offered the Login/Register page before proceeding. Only after logging in can they post a Buy Now or Make Offer bid. We will record their Buy Now or Make Offer transaction to the database for future processing by the Back End, and the logged in Visitor should be able to view their Buy Now and Make Offers made. This doesn't need to be sophisticated. Just the date, whether it is a Buy Now or Make Offer, the domain name, and the Buy Now price or Make Offer price. There is one other page coming off of the search results. The Domain Details Page. This also needs to be converted to WP and modernized. Colors, fonts etc will be as per WP template. Not as you see in the old website. The page will have a Buy Now or Make Offer link depending on what is set in the database for that domain. This Details Page is also the landing page for domains which are redirected to the website. So it must be reachable by a url visitor. ie: [login to view URL] (this might not be truely accurate presentation, but you get the gist) There are 2 small existing CSS problems with the searchbox. 1) When you click on a column to sort it, the CSS is adding an "a" into the searchbox and searching for all domains having an "a" in it's name. This "a" needs to be removed from the searchbox search. This was a bug introduced by the previous developer. This needs to be fixed. 2) The column headers and Domain Names seem to have the same color spec. If you change the color in the CSS, both column headers and domain names change to the new color. This needs to be fixed. But anyway the search results will take on the Theme's color scheme. If you need any more discussion before quote, feel free to message me.