Services play a big part whether you would choose a monthly subscription or yearly. Most hosting providers offer a discount for yearly packages also.
IMO: I would suggest finding a reliable hosting provider, try their services for a few months and if you feel comfortable with what they offer, invest in a yearly subscription due to being eligible for the yearly discount, locked in prices, stability (not having to miss monthly payments) and so forth.
Always preferred monthly myself, as stated above, situations change and I don't know where I'll be in 12 months myself let alone the business I'm paying.
Depends on whether ot not you assess the purchase as an asset, if it's worth it and adds value to your business such as an owned billing license like WHMCS, go for it. Things go wrong, you can always sell it and move on.
Hosting contracts, they're a bit different so I advise anyone purchasing an annual package to take a look at the fine print, if things do go wrong, you can see yourself having only paid for something a month ago with 11 months remaining and it's already gone.
I prefer annually if it is on the smaller side like shared hosting with a reputable company. It saves me time when I have to look at monthly bills and it saves me money over the term. Yearly cycles are good for me because I don't have to worry about an interruption in service when I forget to process the payment for the month.
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