This is probably a bad assumption. A change in the offer price does not reflect on their trustworthiness. You’re also tricking yourself because someone wanting to lock you in down the road and raise the price won’t do it up front, they’ll do it later.
An offer price can change due to market conditions. The statement that price can’t be guaranteed is an optimistic speculation that sales or costs might jump, so you can buy now before their business increases and prices rise due to higher costs or demand. You can legitimately benefit if you buy before prices go up. You certainly can gamble that prices won’t go up, but if they do and you waited, it doesn’t mean the other party can’t be trusted, it means you lost the bet.
If you wait and get a higher price, that could even be a sign that the company is more trustworthy than if the offer doesn’t change. But of course there’s no guarantee. And ultimately there is no guarantee that when you buy a service on a limited time contract that you won’t have prices jump later when you’re ‘locked in’. It would be quite silly to not expect the renewal price later to rise for a variety of reasons, and you should have contingencies in place and be willing, able, and ready to switch providers.
