Even 10,000 units seems like a lot. 

If they’re selling for a $400k+ gain they could look at a 1031 for:A super nice 2-4 unit they wouldn’t mind living in a unit of where the rental portion exceeds their 1031 sale. 

I tend to do a quick dirty look at a building like JW with price per door, but after that sniff test, I quickly like to understand $Cost/SF and $rent/SF.The way I look at a single family, 2-4 units, or a 20 unit is all different, but the end result is still ROI or IRR (over time). 

I don’t know your living situation or if there are any nice 2-4 unit buildings in the area you’re moving to.

we invest in value add plays (no major rehabs) 10-40 units.

Either way its good to buy end of year as most builders and sellers are offering seller credits or builder credits to use towards closing costs or to buy a rate down to help get a lower payment.Even if you wanted to buy a strater home like a 2-4 unit as a primary again you only need to put 5% down. 

He's seen me grow to four units (3 properties) and I'm thinking, there's gotta be a guide or book that would help him just follow step-by-step how to rent out his existing property and buy a new one.

The $56-a-unit process requires landlords to be up-to-date on their property taxes and for the properties to be free of any safety or building-code violations.Since landlords are not legally permitted to collect rent from tenants of a home with an inactive license, the system is designed to serve as a check on property owners, forcing them to address safety violations and pay their taxes.But Philadelphia’s Department of Licenses and Inspections lacks the resources to hunt down property owners who flout those rules, said Karen Guss, a spokesperson for the agency.

HVAC unit is package unit on right side of the unit.

The positive is you can get them out with 60 day notice so 60 day escrow would allow the unit to be delivered vacant (assuming zero issues terminating the rental)good luck