I am bidding on the lower end due to me being new to this site not due to lack of experience and knowledge. I'm trying to build up my reputation here.
That said, what you say is doable. I can take a look at different plugin options to reduce the timespan and costs of doing this, but the likelihood if you want it done right you should have a custom theme. This does, in general, take time but I can try to do it as efficiently and quickly as possible for you and work with you in a way to keep costs down.
To give an idea on where I come from:
I started out as a web developer coding themes and plugins for WordPress so for me this is where my beginnings are. I do know PHP, MySQL, how WordPress itself works, etc. But I also have experience beyond WordPress including javascript frameworks (ReactJS, ReduxJS, etc), TypeScript, NodeJS, MongoDB, and have even dabbled in Amazon Web Services. I'm also experienced with SCSS and have incorporated its use into themes that I've built in the past (though it has to be pre-compiled before use, but it makes designing the CSS of a site VERY easy and quicker). I have a certification in Web Technologies through the British Columbia Institute of Technology and my first time in university I had majored in Creative Writing.
If you work with me, as I said, I'll do my best to keep the price low. Partly because I am new to this site so as to build up my reputation.