How much is $100 of common charges worth?

not necessarily -- the maintenance charges can change in a nanosecond. Is Apt. B undermaintatined? those savings can add up.

Figure out how much that $100 represents in what you would be paying down a 30 year mortgage with.
It sounds like you may be a tad high, only because I recall figuring out $1000 per month difference representing 250K to 300K on the purchase price for me. 10% of that ....$100....would translate to 25K to 30K.
But your def in the right neighborhood for your assessment if ALL things are equal in your comparison.

Take a $1MM purchase, at 5.5%, it comes out to about $175,000 in additional purchase price to get the same payments. But manhattanfox' point is a good one, all things are never equal. Maintenance can change quickly, need to look deeper into the reserve of the building and what condition it is in. The purchase price never changes, but the disparity in maintenance can adjust quickly

Sorry, that $175,000 is for $1,000 in maintenace difference, $100 should be $17,500

Trying to consider the payments net of taxes here...

Borrowing $37,750 at 6% int over 30 years, your monthly payments will be $222/mo. $39 goes to the principal payments (in the beginning of the mortgage), $184 goes to interest. If you are getting AMT-ed, that's a 35% federal rate and likely a 10.5% city+state rate. $83 should come back to you for the tax deduction when you file. So... $222 - 39 - 83 = $100/mo of wasted money.

So $100 of maintenance would be worth about $38k. How's my math?

you're math is faulty as the 6% rate is high. if you get AMT-ed, you'll end up being able to deduct less then the full amount. i'm not sure if you can apply the mortgage interest to the city/state taxes either.

I think you can deduct the interest from state + local as an itemized deduction.

If the mortgage interest was lower (say 5%), the sales price differential would go up even more. I'm coming up with $100 of maintenance ~ $41,000 of sales price.

That's $229 payment less $46 principal less $83 of interest deduction.

you are going to assume the delta lasts in perpetuity?

Comparing maintenance is so hard. Do the buildings have identical services? Are they in identical conditions with the same ages and planned replacement cycles of the major expense items? (Elevators, roof, boiler, etc.)

It may be worth comparing your share of the underlying mortgage and possibly property tax, but the rest is as much art as science. The building with $1,000/month maintenance could very well result in a positive delta versus the building with $900/month maintenance over the long term, if the latter is hit with special assessments, large increases, etc. And/or if the former includes services (e.g., a gym) that would cost you extra if you bought on your own.

To me, +/- $100 in maintenance makes no meaningful difference on its own. I'm looking in the $750-900k range, and +/- $300 or $400 is where I start to ask questions, +/- $500 is where I want obvious explanations (some of which are quite reasonable IMO -- e.g., building has a gym, brand new elevators, new boiler, and new pointing), and +/- $1,000 is where I say no way, regardless.

thanks. this is all helping me think through it.

lad - my main point is that i only want to compare one number, not two, when evaluating between properties. if one apt is $1M and has $1,000 of maint and another place is $1.1M and has $1,200 of maint (and better amenities) it's simpler to say that the 2nd apt is actually $180k more expensive, not $100k + $200/mo, after equating the maintenance charges.

Look fender73, here's a good way to think about it.

Let's take that hypothetical $1M apartment w/ $1000 maintenance. You could probably rent it for $4000, maybe $3500 if you try hard, but let's just go with $4000.

One line of thinking would be you're paying $1M to save $3000 a month, and the $1M stays fixed while the $3000 grows with inflation (which is how both maintenance and rents tend to grow). Taking that ratio, you should be willing to put up $33K for each $100 saved. It's self-consistent with your willingness to buy at $1M. The value of that money is given by a 3.6% interest rate. Simple enough.

Another line of thinking is to ask what the value of that money should be. For the sake of argument, let's look at the cheapest-of-the-cheapest, effectively-no-money-down, all-the-risk-of-loss-on-the-lender-and-taxpayer, heavily-taxpayer-subsidized-rates FHA loans. I choose that because they don't come any cheaper. Even there, they charge a 5.25-5.50% for a 30-year fixed. Thus, even the most heavily subsidized is saying that the value of that money should be at least 5.25%, or only $23K per $100 saved. Another set of assumptions would lead to something like $18K per $100 saved, but let's just go with $23K.

Unfortunately, once you go down that line of thinking, you should quickly calculate that the value of an apartment that saves you $3000 a month compared to renting should only be worth $690K max. Granted your rent will go up with inflation, but there are other issues that counter this. This, along with other issues related to how prices will be affected once support for artificially-low interest rates are taken away, make many of us think that buying now is a bad financial decision.

However, if you've made that financial decision, then I think the consistent number for you is $33K per month for each $100 saved, simply because that's what you've actually decided to spend by your willingness to buy a $1M + $1000 maint condo rather than rent it for $4000. If you think my numbers are off, simply plug in your own, and you'll get a self-consistent number. It's not necessarily right in an absolute sense, but it is right relative to your other decision.