There’s a large apartment (a few hundred units) being expanded 3 blocks away.

If you're lucky enough to find an interested seller, you will need to have the tools to quickly analyze the deal, understand if the sellers motivation to sell, pain points if any, and genuinely see if you can provide them with a quick exit strategy.

Are they a pain to service compared to standard machines?

The only time there is pain is when you TRY to make things work. https://www.zillow.com/homedetails/1377-Sonoma-Dr-Altadena-C...https://www.zillow.com/homedetails/2182-Grand-Oaks-Ave-Altad...https://www.zillow.com/homedetails/1845-Coolidge-Ave-Altaden...https://www.zillow.com/homedetails/1500-Carroll-Dr-Altadena-...https://www.zillow.com/homedetails/1170-Morada-Pl-Altadena-C...

I type “questions1” in my iPhone and it replace it with all of the questions I want to ask.Setting up showings:Do as many as you can in a one or two hour block.

Our software (streamline PMS) can grant multiple users access to owner blocks, calendar, payments, etc

The main block I have with multi family (which is the route I had intentionally intended on going ) is that because I already own a single family, I would need to come up with a substantial down payment and multi families around my area are 800k +.

Yes, it's hard and there's pain and sometimes treatment required.

If you are working directly with sellers, my best piece of advise would be to find out what they need, generally there is a pain point or some sort of distress either in the sellers personal life or with the house itself.

Investors (rightfully) always want to keep their costs down and there are clients who will try to put my commission on the chopping block.