My vote would be for family or close friends who you know and respect from earlier than your current venture.  

I currently use TenantCloud, which I think works pretty well for self-managing DIY landlords, but it's not meeting the needs of my property management anymore (I manage close to 70 units).

This likely would come close to the cost of a ground up 3/2 ADU addition which is rare.  

Say $10k or 5% of the agreed upon future sales price.

Each option has its pros and cons, and I'm hoping to get some insights from this community to make a more informed decision.Option 1: Building an ADUPros:Increased Property Value: An ADU can significantly increase the value of my primary residence.Control and Proximity: I can closely manage and maintain the property since it's on my land.Potential for Higher Rent: ADUs in bay area can fetch a good rental price.Flexible Use: ADUs can serve multiple purposes – home office, guest house, or rental unit.No Additional Land Purchase: Utilizing existing property means no extra cost for land acquisition.Foundation improvements: I will get an upgrade for my foundation which increase house stability.

, so it’s a class close to home. 

. - I never, ever heard of 10% of the renovation funds due at closing and I've closed 100s of bridge loans with many different lenders.I think there's way, way better terms out there but I do not know your credit, if it is good these terms are way off.

This property is close to the down town, near a bus line, and fit the business model.

@Dave Foster can tell you for sure but I believe you’d be okay on any “gain” realized from the sale of the replacement property but you would still of course owe taxes on the gain from the sale of the first property, that were deferred.

Purchase price: $70,000 Sale price: $210,000 Purchased this property from family of the deceased owner , it was in bad shape and was full of cats and debris .