Create online dating site
As your site catches on and it gets more traffic, a cheap service is going to get very slow very fast.You'll then have to upgrade to a dedicated server, which will cost you much more.
In your business plan, draw up a profile of who your ideal first clients will be.
A scalable hosting service is another option, like that offered by Amazon Web Services.
These services also cost about per month if you don't have a lot of traffic, but if your site starts getting popular, the service scales you up and charges you accordingly.
If your niche is for people 50 and over, an app may be optional, at least in the beginning.
But if you're going to cater to anyone younger, a mobile app will probably be more important than your website.