@Shay Reddyblend, extend, amend. you are in better shape then NYC tenants as the city council is in the process of negating personal guarantees that were part of almost all commercial leases (unconstitutionally, and will probably be challenged). first off, i doubt pandemic issues are covered in you lease as force majure. so that is probably a dead end. i am sure it will be a highly negotiated clause in future leases, but not now. the first thing is to do your best to keep the current tenant as i assume your market is not robust with new tenants aggressively seeking space. there are so many questions here.

My experience being a licensed plumber in NJ, I can design plumbing systems up to 3 family before a engineers license is required on plans.

I've reverse engineered the path to my long term goals and will either be wholesaling properties to investors AND my own flip project(s), or just start with a flip.

Please double check that.It may be worth a consult with an engineer to determine the max height you could get without underpinning assuming your contractor does not have the expertise.Also I'm sure you're aware if a dwelling has a below grade bedroom you need a form of egress.

Our typical fee ranges from about $1100 to $6000, depending on the job and the jurisdiction, not including engineering or survey/site plan.

Lisbon and Lisbon Falls have always been a little less robust when compared to other towns in regards to rent and housing appreciation. 

Thank everyone for this very helpful information especially Jay Hinrichs for the search engine.

As an engineering firm we find the FEMA Flood Map is highly inaccurate at the property level because of this flaw (and other flaws).  

Materials aside, land, labor and permit costs all make it more difficult to build at a lower cost in the PNW.No kidding I am just finishing my budget for phase 2 of my project in Canby 30 lots our of our 90 total my costs NOT including the land are  about 70k a lot all in for improvements streets sewer water storm franchise utls  surveying engineering  City fee to build it ( not building permits just the fee to build the infrastructure) Platting final monumentation construction staking appraisal escrow and title fee's for the construction loan  Loan fees and interest paid prior to the actual vertical loan going in. 

You might want to reach out to some of them and they can fill you in on some of the particulars with old homes, but I have seen homes from the early 1800's, maybe a couple of facelifts and a structural engineer or two but, they're still standing so best case your home could have at least 80 years before it comes crashing down.