Looking for a structure that is fair for both parties.

You'll be surprised the type of creative structuring in deals you can come up with that end up being beneficial for all parties involved.

Is there a way to structure this exchange where he would use the proceeds from the property exchanged for 1/2 of the purchase price and use personal funds for the remaining 1/2?

BP,I have folks that have expressed interest in investing in my projects, but I am having trouble figuring out how to structure the agreement since I like to buy and hold.

There are numerous ways to structure it, the most common is a 1-5 year balloon payment where you'll pay them the balance you owe by refinancing with a bank, but you can get as creative as you want with it!  

The other unknown factors (not listed in your post) are if any structural framing, roof or other big ticket items are in need of replacement as well which could add to your costs per SF.For a real and accurate answer, best to get 2-3 contractor bids.

Year of the house does not define if the sewer line was ever replaced the date that structure was built.

While we won't give up, I am wanting to explore the option of purchasing land to build multiple glamp sites, small structures and eventually a small site built home (I know this can take TIME). 

Basement storage is very uncommon in this area and would be a continued nuisance for us re: pest control, utility replacement, and addressing the work we have planned on the building which includes structural work in the basement. 

I am seeking recommendations for a structural engineer in the Chelsea, MA area.