theyll help you with estimating what it might cost per unit)-actually visit the property (with someone knowledgeable) and assess the condition of the expensive items (roofing, heating/ac systems, foundations, plumbing/elec, etc).some of these things will most likely be req'd by whoever your lender is anyways. of course some sellers wont oblige the requests for such detailed info until theyre confident in your offer/ability to purchasealso, sometimes people only look at their buying plan. you want to have a further view and have a plan on exiting (selling it when youre done). how you finance it can impact this because youll want financing that's favorable not only to yourself but to a future buyer as well.being able to sell it off as easy as possible is an advantage and you should always think how you can approach a property thinking "how can my actions help the property be worth more in the future and ease such a sale/transfer when im done?"

Since lease turnover controls your timing, it usually take at least two rent cycles to make a significant impact.  

Lastly, It  doesn't account for regional differences in costs so those in low wage markets may see a big impact on the cost of goods and services.

While the areas with bad schools and perhaps some crime issues like the gentryfying neighborhoods in DC...Petworth, Brightwood, Ivy City, Brentwood....will have huge price variations based on the condition of the property.Now do flips happen in Fairfax and Montgomery County...sure, but in nowhere the same types of numbers that they happen in DC and PG County.It doesnt really speak to Dunkirk exactly, but I hope it sheds some light on how doing X, like rehabbing a bathroom could have a huge impact in location Y, but no impact in location Z, and thus why you can not really have a rule of thumb that spending A will return B. 

Just natural appreciation/inflation are going to have a huge impact over 30 years, and could vary quite a bit between what we expect now, versus what we actually get in the future. 

I am not sure you mean when you say "where" we use it, but I can give you a high level of a lease option is, but I would caution you on you structure anything like this, as there are some Dodd/Frank Acts that impact how these can be done.  

Thus, the only projects that could make a meaningful impact on supply are the massive condo and rental towers being constructed.  

There is still much controversy over the legality of that product in California.The city of Los Angeles, and many other cities in So Cal, have taken strong stances against tenants in buildings concerning their use, their occupancy permits, and their stringent review of the premises which may or may not impact the landlord depending on the city's findings.I'm in the CRE business and I won't have anything to due with this type of tenant.

That impacts anyone...and most here probably wouldn't jump back into debt after that either. 

Hoa fees will really impact you there and I have seen them vary from $200-$400 a month.