Florida is a unique state for MHP law and the insurance has gotten very expensive there too.I recommend checking out @Frank Rolfe's mobile home university content if you haven't already.

Two of the biggest challenges I face are that I’m not very liquid at the moment, and the Seattle area is extremely expensive.

You need to minimize upfront expenses because 100% of your investment is at risk and lost if the lot is not buildable.My favorite strategy is to locate the property and tie it up for usually no more than $100 for a period of 8-12 months, analyze it myself and if I believe it to have a chance at being buildable I create a permitting plan and market the property to other investors/builders willing to take on the permitting risk.  

Analyze potential deals by estimating the After Repair Value (ARV), repair costs, and total expenses. 

Recommend having an attorney review it to confirm.If the PMA has legally expired, then the PMC is in the wrong - although they may still have claims for covering the legal expenses.

Those agents have their ego at the expense of the relationship, and there are such agents actively participating in this thread.

Perhaps you start a side business or go all out on cutting expenses that are sacrificing things that you want.

So it's a pure expense.

@Vidit Maini Starting your business as an LLC taxed as a C corporation offers flexibility but involves double taxation unless you elect S corp status, allowing profits to pass through to your personal return.For tax savings, deduct startup costs, track business mileage or vehicle expenses, and consider a home office deduction.

As far as being expensive; if the tax liability is not large enough then yes I agree, however, it depends on what is being sold too.