Magento - 3rd party modules compatibility and maintenance (over a time)

[adminzakref100]

Currently we use SaaS platform and I keep doing online research to find a really good platform to migrate to. We run a small online shop, so obviously we are not going to purchase Magento Commerce (not yet) 
As far as I can see Magento is a quite robust and secure platform. And I do realize that we need to spend some money to purchase some quality modules, themes and so on.
What I'm afraid of is life cycle of Magento and modules versions and related maintenance. I mean some modules update might stop receiving updates or be incompatible with other vendors.
What's your experience, can you recommend modules vendors/developers that we can rely on for at least couple of years?

EDIT:

What's your opinion about i.e. Magesuite and Sparsh modules? After quick testing I have mixed feelings...

[sam6c0a]

If a vendor can earn enough money, they will continue to offer updating and maintenance service.

We can recognize a vendor can earn enough money If the vendor already developed many good selling extensions on the official marketplace.

Unfortunately, we can not tell if an extension is selling well or not directly. We can only guess about it.

In one word, The bigger vendor is more stable than the smaller.

That's my own experience.

Hope it's useful to you.