This website would have appropriate links to information on all devices.Security - External camera(s), especially at the entrance, that records and retains video (cloud) for an extended period.

Can it just be recorded as an owner contribution?

As long as everything is recorded correctly and all documentation is done, there are ways to do this. 

Anonymity is not asset protection, never has been and never will be and as others have mentioned the Corporate Transparency Act, recorded instruments or simply waiting for that claim to be filed and completing the discovery process will reveal who you are.

2) PS specific home - We looked at a few and were intrigued by one that is a 3/2 (plus self sufficient ADU, former garage) with a nice pool, yard but 2/2 on city records.

Open a personal account, use their banking services & if you can demonstrate a track record of executing on the real estate loans they fund for you, these relationships can really accelerate your growth.

I know sellers who find a buyer with a track record and the seller does seller financing so there isn't a big capital gains issue (plus they're making money on interest). 

There are many Business Loan Applications, which are virtually identical and carefully worded, that you can find online.Hopefully, your lawyer includes a Certificate of Non-Owner Occupancy in your loan package, and language to that effect is liberally mentioned in your note and mortgage/deed of trust.Consider obtaining a script offered now by some lending attorneys that you can use to interview your borrower about their intent during a recorded Zoom call.

They will wait 7 years for it to fall off their record.

However, the seller claims he purchased the property as a two-unit dwelling based on Baltimore City public records, yet it’s not legally permitted as such.