There are auctions to sell cars, police auctions, tax impounded auctions, antique auctions, etc.

In NYC trying to compare like properties and eliminating co - op debt, co-ops will sell for 60% to 200% of a comparable condo.  

If selling properties, a 1031 exchange defers capital gains taxes by reinvesting proceeds into another investment property, while Opportunity Zone investments can defer or eliminate capital gains tax over time.Long-term rentals should be held in an LLC for liability protection and tax efficiency.

You are only adding complications and costs with the LLC with no upside  This is all assuming there’s been almost zero appreciation and you shouldn’t sell tax free while you have the chance. 

So in my mind it would be best used as a last move into a REIT you never sell.  

new houses are getting sold for 600K, old houses switched to multiple offer selling model, just like some places in GTA.

Any development work they've done on the property also becomes your property.If the property becomes yours, you could try to sell it back to them quickly and below market for a nice profit.

They would either be capital improvements or costs of selling, most likely. 

Try being an agent, your phone number is EVERYWHERE and you get targeted by a whole industry that wants to sell you the latest gimmick.Here is what helped me.I answer calls and when it's a telemarketer I will interrupt them and say very friendly (because I don't hate the poor person who gets paid to do this and coached to be ruthless): Hey, so glad you called, can you do me a big favor? 

Is your client building to rent, or build to sell?