I'm buying a property directly from the owner. 

That said, long-term the appreciation you get in the Puget Sound region is superior to many other markets, so assuming you find an excellent property management company that is able to screen tenants and only put in very well qualified, vetted occupants and you experience limited issues over the holding period, you'd likely come out ahead retaining the Mill Creek property if your financially able to do so and still buy wherever you are headed out of state.

I'm a new investor in buy and hold RE. 

I've been doing some research on buying first rental property in Port St Lucie Area. 

To ensure I navigate these legal aspects correctly and make informed decisions, I’m looking for recommendations for a knowledgeable real estate lawyer or legal entity in the area.

Investment Info:Small multi-family (2-4 units) buy & hold investment.

More information on this below.

Engage architect/civil engineering - If you are buying land to start development and not just land-banking, I'd engage with an architect immediately.

Is there a way that sellers should validate this information?

I want to buy a new private home and use my current primary residence equity (plus some cash) to buy a new primary house cash and then sell the old one.So, I am looking for a HELOC with little to no closing costs, as I will retain the money only for as long as I am selling my old house after buying a new one.Any advice?