Create a WordPress Template from PSD files

We have a complete PSD look for our new website which will be hosted on the Wordpress/WooCommerce. We want a native Wordpress theme (+child) in a way it can be upgraded/updated as the Wordpress evolves. This also means we need a partner who will also be responsible for future upgrades/tweaks, etc. This has a potential to become a longterm partnership. Website/store consists from landing page + store subpages and it's concept is clean and minimal without unneeded ballast. Basic filter needed with sliding/following cart always visible. We already have full dedicated graphic expert so PSD template is already fully prepared (not sliced since this represents troubles for some). If additional PSD work is needed, we provide.