This may result in some existing STRs no longer being legal. 

Why not just find an existing duplex to house hack?

I would like to update my rental rules to reflect the 8 days/30 days verbiage in my lease but I am unsure if I can do this for existing tenants as well or do I have to wait for each new tenant?

For example, my first flip of an existing triplex we averaged $75/sf in West Philly.

. (~$200 - $400 monthly)Current net cash flow from existing REI will cover construction time related carrying costs Phase 2: Post Construction / Tennant Occupied Rent the three units for $1200 each unit / $3600 total (our team feels we could yield ~$1300 – $1400 per unit present day.

Purchase price: $165,000 Cash invested: $10,000 This Tri-plex had existing long term tenants with a history of paying rent.

My answer is speaking generally, so please nobody get bent out of shape or take it personal...The existence of consumer debt indicates bad money decisions in the past.

If they don't even offer 75%, then seek another lender.And the main reason we want 75% of ARV is because on the conventional loan they will refinance the existing lien AND ROLL IN CLOSING COSTS. 

Can I be added to an existing conventional mortgage on a primary residence?

Being a scarce resource, opportunities like this may not exist in the future, or may get priced out.Due to the recent fleeing from cities, not might be the right time to buy a condo, instead of houses which have shot up in price.Your thoughts?