TradePMR has had a veyr long standing referral partnership with RIA in a BOX.  I know Zachary Gronich well and they are a good organization.  As far as custodians, best to shop around and find the best "fit" particularly their services and technology.  I've heard good things about E-Trade from some.

Attached is a sample checklist you might find useful as you plan your new adventure as an RIA!  Best wishes to you and your family.

I don't think E-trade offers custody service

If you want it cheap, I would also recommend Peter Mcphee for application. I just got it approved

Peter McPhee, 208-773-5601 (summer) 757-220-2166 (winter).