A numbers approach.
Since I don't know your exact numbers... I am using estimates, and if they aren't very close you will have to recalculate.
227,000 at 4.125 for 30yr is 1,100 a month. Because you said you put little 0% down and still are not below 20% LTV, pmi is ~100. (this may be wrong, but I will use $100 for simplicity)
Property taxes are assumed at 2,000 a year. This is probably lower than true number, because you say a "few" grand is 7 months...
You paid $62,000 in interest so far. Along with $8,600 in PMI, and $14,000 in property taxes.
You are near break even in equity. So all your "principle" portion has been lost. It has cost you $115,000 over 7 years to live there. Which works out to $1,366 a month.
If you stay and continue paying 1,100 a month (plus $100 PMI for 3 more years until @80%) you are looking at 107,000 more in interest over 23yrs. To change this number, you would have to increase your payment above 1,100 (dropping the $100 pmi after 3 years). $1366 a month for 3 more years, then 1266 a month for 20yrs. $353,016 over 23 years. At which time you have a 210,000 asset. So, $143,000 in lost money.
Assuming you sell for $209,000 and pay closing fees of about $1,000 (rough cost of title insurance) and a 3% commission to both seller and buyer, selling costs of $14,000. You are looking at $195,000 and then adding 1k and netting $-1000.
You have $27,500 in cash. And are willing to hold back 8,500 in roth contributions.
Moving costs are on average $1,100 for a short move like you are planning.
Plus various costs with a new house... 2k-5k I would say to be safe.
27,500+8.500+1,100+3,500= -40,600 + -1000 = -41,600
So I estimate that the move will cost you 41,600 immediately.
Now to look at the savings :)
Mortgage payment on new house is $680. Taxes are less. I will assume $1,800 a year. So $830 a month = +$535 a month or $6,420 a year.
30yr 144k at 3.9% costs 100k in interest. Very similar to your current 107k remaining. Due to you being 7 yrs into it is why the similarity. (note, payments are not the same 680vs1100)
Adding $420 to your mortgage payment (thus keeping your payment @ 1,100/mth) will save you 57,000 in interest (43,000 in interest). Payoff date is 14yrs 4mths. After which you only have taxes @ 1,800 a year. So 23yrs will cost...
$231,200
After which you will have a $180,000 asset. So, 51,200 in lost money.
A savings of $92,000
$3600 further savings due to no PMI. And $16 a month in saved taxes which is not added into the equation.
Bringing your total to $100,016 saved.
Your 41,000 outlay will save you more than double.
Another way to look at it, a 4% return on 41,000 for 23yrs compounded monthly is 102,000.
There are other options,
These use a 10 year outlook vs 23.
Lets say you jump up your current payment to 2k per month on your current home. You pay off your 196,000 in 10 years, with 43,400 in interest. A total of 240,000. Plus 20,000 in taxes. Ending with $210,000 asset = $50,000 lost money.
You buy new home, pay 2,000 per month and pay off in 6yrs 11mths, with $20,300 in interest. For a total of 164,300 + your down payment 36,000 = A total of 200,000. Plus 18,000 in taxes. Ending with $180,000 asset = $38,000 in lost money.
$12,000 positive.
$13,100 with the PMI savings. (paid off at 11 months @ 2,000/mth)
Would you invest 41,000 at 3.2% simple interest for 10 years?
One last thought. Your downpayment portion of the 41,000 (36,000) isn't exactly a "cost" it is an investment. The "cost" is the 5,000 in direct expenses.
It is also my opinion that you will recoup the -8500 IRA. As you are only shifting the money for a tax free investment account to a tax free personal house.
This took a lot longer than I had planned. I hope it makes sense. With the savings I see over the longer term... plus your desire for a larger more comfortable place. I think this is a positive change. One that will make sense for your lifestyle and finances.