Once you know what the city will allow, or more importantly not allow, your Realtor can then determine the lots highest value. If you are in downtown I have to believe you are selling commercial, or at least that is generally going to bring the highest value. Either way you will know the answer then.
It will be very difficult to determine value without knowing the legal side of things. Hope it works out though! If you have any other questions feel free to contact me.
The Duckwall Team of Realtors
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Your best plan of action is getting an analysis of what your property would be worth without the extra land, and, what the split off property would sell for. If you choose to to sell it that way, it's best that it's done prior to putting it up for sale as there are a lot of actions to go through to actually get it split if you feel the two values are significantly higher than selling it as a package. A buyer will not pay full value for a lot that has not been through the rigorous splitting process, there is just too many unknowns, i.e. will the county/city really allow the split - there are always nuances that show up during the process.
Your lot is very large for the area but with the location of your house in the middle of the lot, it would be difficult to split side by side lots. Your best split would really be a front to back split, but I think where you are going to struggle is that there is no good way to get access to the back of your lot like your neighbors to the east did. Nonetheless if you would like to have a conversation about it, I have worked out of the White Bear Lake area for over 10 years and have experience with splitting lots in the city in the past.
Keller Williams Premier Realty
p.s. There is some decent demand in WBL depending on where you are located. I also know some builders who might be interested too.