Technically, I would suggest the Tamron 28-200mm f/2.8-5.6 Di III RXD for your budget.

• It has a unique f/2.8 starting aperture at 28mm.
• Resolving power is high for a versatile travel zoom. Be careful with the variable aperture tho, as it drops to f/5.6 fast when you zoom in. Make sure to monitor your exposure when light starts fading in those narrow alleys...

If you want the best balance of range and technical quality for Italy, you gotta look at the Sony FE 24-105mm F4 G OSS! I love it because that extra 4mm on the wide end is huge for architecture. Constant f/4 aperture is amazing for consistency too. You can usually snag one around $1000 on sale. Its a beast. Seriously. The built-in OSS is super helpful for low light shots in churches...

Saw this earlier but just now responding. Honestly, those massive zoom ranges like the 28-200 usually end up being a disappointment if you actually care about technical performance. I tried a superzoom on a high-res body a while back and the chromatic aberration at the long end was just a mess... really frustrating when you have a sensor that shows every flaw. Youre basically wasting the potential of that a7iv. Id skip the superzooms. I switched to the Tamron 28-75mm f/2.8 Di III VXD G2 and the difference in micro-contrast was huge. You lose reach, but f/2.8 is vital for those dim Italian cathedrals where a slower lens forces your ISO through the roof. If you need more range, the Sony FE 24-105mm f/4 G OSS is technically better corrected, tho youll have to look for a used one to stay under a grand. I just wouldnt settle for a lens that compromises image quality that much.