Two ways to be cheap
Hostinger gets its low three-year cost from the length of the intro term: 48 months at $2.99 means the $10.99 renewal never appears inside the window. Namecheap gets there from the renewal itself: Stellar is $2.28 a month for the first year and $4.66 a month after that, so even on yearly terms the total stays under $140.
The practical difference is the commitment. Hostinger's price needs $143.52 up front for four years; Namecheap's needs $27.36 for one. If you are unsure the site will last, Namecheap is the lower-risk way to start.
What is included
Websites and storage: 3 websites and 20 GB SSD on both entry plans.
Domain: free for the first year at Hostinger; not included at Namecheap.
Backups: weekly on Hostinger Premium; Namecheap's AutoBackup is included from Stellar Plus upwards.
Bandwidth: unmetered on both.
Money-back: 30 days on both.
Control panels and locations
Namecheap uses cPanel, the long-standing standard that most tutorials assume. Hostinger uses its own hPanel. Both have one-click WordPress installers. Hostinger offers more data-centre regions (US, UK, EU, India, Singapore, Brazil) against Namecheap's US, UK and EU.
Who should choose which
Prepaying four years is fine: Hostinger Premium. Lowest three-year cost and a free domain.
One year at a time, lowest renewal: Namecheap Stellar. Add Stellar Plus for unlimited sites and backups.
You already hold domains at Namecheap: keeping hosting in the same account is convenient, and the renewal price makes it a sound long-term choice.