Standard 1” residential HVAC filters are complete junk. Any time you re-do an HVAC system, you should upgrade the filtration to something decent.
I just glanced at Consumer Reports, and they like Aprilaire. As it happens, I put in an Aprilaire when I replaced my upstairs system about a dozen years ago, and another on the downstairs system in 2020. I’m very happy with them. It’s not serious large building commercial level, but it’s close. I change them out annually, and they’re about $50 each.
If you want to go serious commercial level, what you want is a 4” pleated media setup using Merv 13 or 16 filters. And if you want true hospital grade, bring money and space, because you need room for a 4” pre filter and a 12’ HEPA filter. And most residential systems can’t handle the pressure drop.
On any of these, make sure the installer gets a big enough one so that the resistance to airflow is low enough that the system can handle it. Don’t skimp on surface area.
SB 12” HEPA filter, not 12’, in case anyone is reading closely.