fence - property issue

question about our options and overall...what we should do??

we recently moved and love our new neighbors. they're happy and friendly and perfect. our backyard fence eats into their property (most likely unbeknownst to them...as they seem very clueless and carefree). we just found this out when we had a fence co come out for an estimate - on extending fence along side of property.

the property is a diagonal line, but at one point (far corner)it's SIX FEET in their property. we have a small yard, the neighbors do as well. they never use their yard (like EVER EVER EVER & it's been completely overgrown for years and years) - as their kids are fully grown..etc. (they completely live on their front screened in porch). we do use our backyard daily, especially that side of property. the property lines - in general - are very funny here (very diagonal - a lot of funny uneven lots) and as the property line runs towards the curb, it eats into what looks like - should be their property (almost rt in front of their house). weird, rt? anyway, we heard they are talking about moving . we are wondering how - if possible - we can go to them, asking them to consider a swap: we own the back portion (that's already fenced in - for our backyard) & they own the front. i would think, in general, it's so much more appealing to have more of a backyard, than front...so i am skeptical this would work, but REALLY need advice on what to do? -and how much might a lawyer fee be here?? very clueless (& feeling frustrated at previous owner who neglected to tell us this important bit of info. -we didnt use a realtor and she was a friend). help?!?

Neighbors on our street did something similar. Neighbor A bought a strip of land from Neighbor B just before Neighbor B put their house up for sale. (Also had unusual wedge-shaped lots.)

The purchase of the additional 4' strip of side yard gave them enough set back to build an addition they had always wanted.

It just boils down to money. How much do you want to spend to guarantee your back yard will remain the same size?

Make sure this is done legally and officially. The lot maps for both homes will have to reflect this, as will the tax reassessment for both parties. You need a lawyer to ensure this is done properly and filed and approved with the town, county and perhaps even the respective mortgage companies to ensure that you and your neighbors don't run into issues when you each sell your property in the future.

thank you