How do remote workers maintain a professional business address without renting office space?

I’ve been working remotely for a while and usually use my home address for contracts and invoices. While this works day-to-day, I’m realizing it may not appear very professional, especially when dealing with international clients.

I’ve heard of virtual office services that provide a business address and handle mail forwarding. For those of you working remotely full-time, how do you manage this aspect of your business? Do you use virtual offices, coworking spaces, or some other solution? What challenges have you faced, and what’s worked best for maintaining a professional image?