home depot and lowes is a great way to start . amazon is awesome from small to large items and sometimes have sales . some of the contractors you work with will also be able to source materials from their established relationships of suppliers .

They can network effectively with placement agents - Agents are going to be the primary way a house is filled, so a reputable manager likely will have multiple agents who are willing to work with them already because they have a history of running good homes.

Tenants all tell me they'd much rather rent from an individual landlord, the big PM companies have bad reputations apparently.

I would suspect you would be better off talking to a reputable turnkey provider.

When exploring financing strategies for your first BRRRR project, especially with an owned property, start by researching reputable private or hard money lenders who specialize in rehab financing (like us :)).

There are companies that sell turn-key rentals that could be a great solution for a busy professional, or maybe finding a reputable wholesaling company or realtor to help bring you deals to leverage your time better. 

Steps to Vet a Hard Money Lending FirmReview Their Track Record:Look into the firm's history and reputation.

It's not a waste of money at all if you choose a reputable company.   

I would be VERY careful of syndications you can read all the horror stories currently on BP of investors in once reputable companies now seeing complete losses of their invested capital. 

Rest of San Diego that does not have same history as a STR supplier, still has permits.