it was not about a small fee to renew a visa but actually needing to go abroad (outside Shengen region / EU) which also is much more significant cost.
You don't seem to be listening: going outside Schengen zone only makes a difference to you ability to reside in Poland if you stay outside the Schengen zone for 90 days. Just going out for a day or so does not
get you a new visa. Once you have been in Poland for 90 days (or anywhere else in the Schengen zone) you must either get a residency permit or leave the Schengen zone for 90 days. Is it really so hard to get your head round the fact that visa runs are no longer possible?
I know a city nearby actually only asks for photo ID though the local town I'm in seems to want passport for this which we're trying to confirm.
I would suggest getting married in that city then (at least have the civil part of the wedding there and then do the church bit in the way that you have planned it).