Biggest expenses will be roof repair, flooring, exterior and interior paint, some replacement windows, and cleaning/sealing the interior due to nicotine stains/odor.

Have you thought about staining the concrete?

@Curt SmithI'll make a really broad statement, if you do want to do one or two sandwich lease option deals a year it's not a big deal as far as being licensed, this is only my opinion but I think most "departments of real estate" could care less of 1 or 2 dealsThe big point I'm trying to make is if you want to do 50 to 100 of these deals a year, there's no way around not being licensed in most states because you're acting as a major business operation, there is a pattern of similar business activityAnd I've said this over and over, all it takes is for you to get a negative reputation at the department of real estate in your state which will stain your reputation from being licensed in the future; all it takes is one real estate broker to write a letter to the commission and now you've got headachesIt's prudent just to get licensed and build a business you can be proud ofA sidenote:  I think a lot of people on BiggerPockets think that if you are licensed it stops you from doing creative deals,  that's not true at all.Regarding sandwich lease options on nice houses in nice areas, Dodd Frank excludes your relationship with the owner as an investor, if your subleasing and sub optioningI think there's a great opportunity for you getting rent credits and doing creative contracts with your owner as an investor with sandwich lease options, but don't be broke and not have some reserves like 3 to 6 months in case the tenant buyer doesn't pay you when you sub option and subleaseAnother issue is be careful of who you let into the house and make sure the tenant buyers  work on their credit and save money for down payment and they truly want to be homeowners.

congrats on your journey. in my experience i have refinished hw floors and installed thousands and thousands of square feet of laminate floors. the issue i have found with laminate floors is if they ever require a repair down the road it is unlikely you will be able to get an exact match for the floor you installed  X years ago. hardwood floors can be refinished several times and look great when done right. you assumption on carpet is pretty accurate. we tend to install a mid-grade carpet (not the cheapest carpet available)  and as long as tenant did not totally trash it we have been able to get it cleaned and in some cases even dyed it a different color if we could not get the stains out but yes we replace a lot of carpet after tenants leave. 

The numbers on this deal:Purchase Price: $72,000 cashRehab Costs:Kitchen Granite: $1300HVAC upgrade: $500Electric Fixtures: $800Interior finish: $2300Bathroom: $800New floors: $2800Dumpster: $1000Deck: $3000Microwave oven and elec: $600Rotten wood removal: $895Deck stain: $595New sod: $1795Shutters: $295Concrete stain: $495Mail box: $95Total rehab: $17,270Total cost: $89,270Sold price: $115,000Closing costs: ?

Total rehab: $17,270 (estimated was $18k and change)The numbers on this deal:Purchase Price: $72,000 cashRehab Costs:Kitchen Granite: $1300HVAC upgrade: $500Electric Fixtures: $800Interior finish: $2300Bathroom: $800New floors: $2800Dumpster: $1000Deck: $3000Microwave oven and elec: $600Rotten wood removal: $895Deck stain: $595New sod: $1795Shutters: $295Concrete stain: $495Mail box: $95Total rehab: $17,270 (estimated was $18k and change)Total cost: $89,270Sold price: $115,000Profit: ~$25,730 (after soft costs it should come out to around 20k, need to figure those)DOM: 150They really nailed the rehab budget and for that I give them credit.

This isn't a big deal if you're already replacing the wall board and doing a new tile installation.I would avoid installing a fiberglass tub and surround in a rental because there's a pretty good chance that at some point a tenant will use an abrasive cleaner which will scratch and dull the surface making it look old and ratty pretty quickly and very prone to staining.

If it has black stains , some moss etc , call a roof cleaning company , not a power wash company .

Yes, stained concrete in lieu of flooring can look beautiful and can be done with amazing patterns, but have you ever tried to remove a wine stain (that the tenant failed to clean up) from stained concrete?  

One buyer passed because there was some stain on the handles in the kitchen.