My goal is to stop paying rent and obtain a multi-family in Philadelphia where I can rent out one or two units (I'm targeting a duplex or triplex).My questions are twofold - I'm not too sure how to semi-accurately calculate rehab and I know in a competitive market a 70% ARV is hard to fine.In the Philly area does anyone know a good rule of thumb for a complete gut such as ~$30/sqft. that I can use to know where to set a budget?

Trying to get short sale approval is a semi-lengthy process.

It is in case a semi wipes them off the face of the earth one night. 

There are also a lot of more semi-active investment types that could offer you greater returns, but if you're time-starved this probably isn't a good fit for you.  

So first I'm wondering, which would you suggest for a semi-new investor?

The $75k would get the full +$300 and $25 would probably get an extra $100/month-  Most surrounding properties have been updated to semi-luxury rentals and are getting $1100 and $1400 per month rent for similar sized units without parking.-  Below is one shot at my analysis of the numbers. 

.- Attempted to build a barn out of a semi trailer shipping container. 

But STR laws are semi strict here in Charleston so definitely look into those if you plan on doing str here.

A couple more have backed out of home buys until things subside & are now considering semi-rural rather than the density of suburban 'pleasantville' enclaves.Had another investor tell me his 4 months of Covid-nopay-rent tenants paid everything up to date to avoid not qualifying for a mortgage with a pending 'after Covid' judgement against them.

House needs inspection but seems like in good condition with semi updated all utilities ( 7-10 yrs).