@Jonathan Bock & @Wyatt WolffYes, so my spouse and I have a roadmap for growing our biz and while I've hired someone to help in my day-to-day role, I'll still be doing revenue operations/outside sales/biz dev about 7-10 hours a week.

Tom Wheelwright’s books contain more detailed information than the online courses do.

Comparable sales and engineering studies could get messy.

If you can get a nice premium for the sale you can time it for when the lease is up.

If it is a clean guaranteed $500 a month that's worth a 50k sale price. 

Property taxes could also go up closer to $2,000/month if they were to re assess after the sale.

also how would I go about finding vacant land for sale my city ?

For example, interest only vs. interest and principle vs. interest, principle as well as a certain minimum % of the loan are all types of payments I've see on lines/loans of credit.

If you plan to continue working in houses like this, yes, it's worth developing this skill.Look online for how to use oxalic acid and peroxide cream developer to lighten floors, the actual technique you'll use.

A sale at $700k would still mean you'd be under the $250k sec121 exclusion (since it sounds like you arent' married yet).