Yes to some extent. We wrote a CRM that works for what we needed. It's not a full blown SaaS product we could sell to any company as a tenant, as they would all want other features that aren't important to us. This is what happens during an implementation anyways, we only implement what we care about.

No names, but my company is service companies (mostly residential) - many logos with different verticals (think electric, hvac, etc). Having a SaaS CRM that served all our brands needs was always a challenge and made aggregating anything difficult (we basically were running multiple CRMs)

We were using dozens of SaaS tools per logo - and just going through them all and figuring out what features we need/want and rolling them into the larger system. We've also built handful of things for internal operations, finance, etc