That’s doable, but before anyone can give you solid advice, you really need to define the setup, because “phone farm with remote access” can mean very different things in practice.
A few important questions first, so people don’t give you the wrong suggestions:
How are you planning to provide remote access?
Screen-sharing apps, full device control software, or something custom with USB hubs + PC control? Each option changes cost, stability and what clients can actually do on the phones.
What kind of phones are you thinking about?
Low-end Androids, mid-range devices, or mixed models? Same brand/model or whatever you can source cheap? Consistency matters a lot for maintenance and automation.
How big is the farm you want to start with?
10–20 phones is very different from 100+. Power, cooling, USB management, network stability and physical layout become real issues once you scale.
What’s the use case you want to allow?
App installs, account creation, social media, ad testing, SMS verification, etc. Some use cases require SIMs, some don’t, and some need rotating IPs instead of a single connection.
Are you planning Wi-Fi only, SIM cards, or both?
This affects costs, IP strategy, and what kind of clients you can realistically serve.
My honest advice: don’t start huge. Build a small, stable setup, test remote access, see what kind of clients you attract, then scale based on real demand instead of assumptions.
If you can clarify the points above, people here can give you much more practical advice instead of generic “buy phones and rent them” answers.