Buying existing LTR or STR with proven income that may just need an update or a value add (add more units, add more bathrooms, beds rooms, etc.) and your next one you can try a riskier property that has less proven income.

Although I'm curious, you mention only adding a bathroom to house hack the back half of the unit.

Such as there must be a certain size for a certain bedroom/bathroom count. 

I will be looking at vinyls floors, new cabinets, countertops, windows, doors and bathroom redo.

Just to give you an Idea on some numbers , I am doing a 2100 sq ft house , class A neighborhood ,  clean out , removing some walls to go open floor plan , minor electric , some mid level replumbing , full custom paint , new kitchen , new bathrooms ( 2.5 ) , new windows , refinish hardwood upstairs , Vinyl plank downstairs . 

With a shell, depending on a few things the materials alone can cost 100k before even  bathrooms or windows in.

.- Bathroom surround: white subway tile (3"x6" I think)- Bathroom toilet: white- Bathroom vanity: vanity with top.- Kitchen sink.

We are actually waterfront to a large creek (small river size).I'm located in Warren, Pennsylvania.Comps sold for ($129,900)/($125,000)/($87,000(needed two new bathrooms))/($114,000)/($225,000)/($103,000).  

Septic tanks are rated for the number of bedrooms in a house not the number of bathrooms and kitchens.As a real estate agent, I think the indoor laundry room would sell better than the laundry hookups in the garage and a really small extra room in the house.

The master suite offers a tranquil retreat complete with a spa like like en suite bathroom.