it definitely sounds like it could get messy. 

As in - if you want to take an aggressive position and are not afraid to defend it in case you're audited, then...Here is one possible answer, out of many that could come out of a thorough analysis.the apartments can be considered in service since Oct 2018, so you can probably deduct your entire mortgage interest and your entire holding costs such as taxes and insurancerehab costs should be allocated to the different parts of the property as much as possibleonce each respective part of the property is ready to be placed in service, its portion of the rehab kicks insome pieces of that partial rehab, like appliances and carpets, could be immediately deductedother parts (which is possibly most of the rehab) will have to be slowly depreciated over 27.5 years for the residential units and 39 yours for the shopsonly some work specific to the apartments might qualify as repairs, and it has be evaluated by a tax proYes, it's complicated.

Throw some carpet down?

I would also charge for cats because in reality cats destroy more than dogs if there is carpet in the property.

New tile flooring, carpet, baseboards, granite, paint, bathrooms, doors What was the outcome?

Otherwise you will have an experience like I did where they were using my rent money to buy carpets and blinds etc for other people and for their own properties. 

Our rehab includes new appliances (basic, not over the top), all new flooring (vinyl plank throughout except carpet in the bedrooms), new plumbing and electrical fixtures (including ceiling fans), cabinet repair and painting, sheetrock repairs, new shower/tub plumbing and tile surround, bathroom vanity top and sink, new toilets, paint, and backsplash. 

Yes i have done my calculations and I buy properties that are in decent shape (I look for properties that need windows, flooring, carpet, and paint).

15 years ago I had a PDF that outlined paint colors, carpet brand, cabinet brand, flixture brands, etc.

How much will it cost to paint and carpet a bedroom in your area?