I am carrying the mortgage.

I believe those losses can be carried forward into future years so that when you are making money, you pay even LESS taxes on it and keep more in your pocket. 4.

Copies of leases & all amendments (anything verbal will not carry over - if a tenant fights it, then you negotiate a new agreement with them or they leave - Never make verbal agreements with your residents)2.

Generally, losses from your rental properties can only offset other passive income, and if your passive losses exceed your passive income, you carry forward the excess losses to future tax years.

Selling @ $500kLender providing $490kCan the remaining $10k be carried by seller?

Just wondering what the implications are of changing a single member LLC to a multiple member LLC as far as current depreciation, basis, carry forward losses and any other issues. 

Selling @ $500kLender providing $490kCan the remaining $10k be carried by seller?

Depending on your definition of house hack, these excess losses may be able to be carried forward as passive losses on form 8582 (not enough information to determine this part, would need additional info).I will mention as well that if you choose to switch to another accountant who more specializes in real estate, being that it's April, any good CPA will automatically want you to file an extension.

We haven't discussed terms of his owner carry yet (10% down).

I believe you can carry those loses forward to next year though.