Being tax efficient is very important. 

That would accomplish exactly what you asked - to split the gain and tax across two tax years. 

You could consider using a non-recourse loan for the remaining amount, but you'll need to be cautious about unrelated business income tax (UBIT) rules.

Let’s say we’re shooting for $50k tax saving per year. 

But between my broker fee and the lenders fees, it's usually 2-3% of the loan amount.They're ignoring the $7k escrow for taxes and insurance, for example.

If for example a home is selling for $225,000 it will have an estimate of $1,462/month.With 25% down the calculator shows: $1,023 per month Principal and interest $806Property taxes$125Homeowners insurance$92How can I get a better idea of the total including everything? 

Yes, they are. separate meters and property tax bills.  

We both work remotely and are curious about how long we can stay at the rental before it becomes an issue, wether thats state tax implications or perhaps when our jobs should be notified that were working in WA vs OR?

Let’s say we pay X amount in mortgage.My question is : how do I calculate mortgage/interest/property tax for other house which we have rented so that I can deduct that from rental income?

It would be same as saying you also owe future taxes and insurance.