The size of the payment is somewhat irrelevant (in my opinion, and assuming you have sufficient cash flow to take care of the property).If you want to get more in depth on the cost/benefit analysis, you could use a program like excel to plan out your cash inflows and outflows, set these against a discount rate (essentially a risk-free rate of return commonly based off of 30-year treasury bonds), and determine the IRR (internal rate of return) that the refinance would yield you.I hope this helps.

The only surplus allowed is with the Treasury at the end of the day. 

If you go back in history of the treasury regs and the UCC, based on a test question in finance, long, long ago, that treasury notes were legal tender to pay all debts public and private and any debt can be settled in cash.

And why prime commercial paper yields more than US Treasury debt.  

A junk bond yielding 10% is higher risk than a US Treasury bond yielding 3%. 

The long-term treasuries are screaming higher rates and inflation being heavily persistent, which usually means underlying house values will go up but I don't think we see that if wages aren't supported in the short term.

Treasury notes increasing have already erased the very short-lived drop in rates and now they are even higher than before the FED cut. 

The IRS Treasury Regulations merely require that you have the intent to hold for investment.

That indicates the government support was artificially keeping rates low.Mortgage Interest rates are determined by the treasury note, not other factors.

What’s not apparent at the moment, is how will other components of pricing react – namely, servicing values, MBS pricing, and spreads between mortgage rates and treasury rates.