Renting server rack space for a server I already own

Hello Teksyndicate team! I do some small IT work for a small business in my area. Their database is currently housed in on-site servers. A couple months ago they had a massive DDoS attack, which highlighted the issues of running the lifeblood of your business on-site and with only traditional home-network security procedures. Cloud hosting looked great from far away, but the cost doesn't make sense for such a small firm. Then I started researching someone who would allow you to rent physical rack space instead of the whole package that is cloud hosting. Physical rack space opportunities looked sketchy at best, but I know they exist, so that's a start.

Here's the short version question: Do you guys know of any economical cloud hosting or have any advice for renting rack space.

Thanks teksyndicate for being smart and willing to step into the light and share your knowledge. There are a lot of smart people who don't know how to communicate and as such don't ever get seen.

 

P.S. If you want to answer another related question; is it worth diving into linux server or is the learning curve too steep for a learn through practical use approach: ie. switching from windows server to linux so as to avoid the inevitable windows licensing battle. Is it worth it or will I get swamped.

Thanks again.