Three kinds of address, treated differently by Telegram. The price gap is a multiple; so is the survival rate of accounts behind them.
Datacentre
The cheapest. Hosting ranges are known, and an account behind one draws attention immediately. Workable, but the thresholds are lower and attrition higher. A poor choice for warming fresh accounts.
Residential
Home ISP addresses. To Telegram they look like an ordinary person on home internet. Mid-price, noticeably calmer than datacentre. The sensible default.
Mobile
Carrier addresses. The most expensive and the most trusted: thousands of real subscribers sit behind one mobile address, so Telegram cannot link accounts by it.
Accounts per address
One, on residential and datacentre. Not caution: several accounts on one address get linked to each other, and the restriction lands on the group. Mobile tolerates more, and even there single digits rather than dozens is wise.
When the premium pays
On aged, expensive accounts and on those holding long conversations: losing them costs more than the proxy difference. Disposable accounts on short tasks do fine on residential. Saving on proxies is always smaller than the accounts it costs — more on the automation page.