Your best bet might be to see the house and make the offer there, so you can negotiate properly (without highlighting TOO much the deficiencies of the property) with the owner.

I used to use regular #10 envelope (standard business size) 4 1/8" by 9 1/2" to stuff my yellow letters.

Price will depend on many factors that I don't know( rot, custom sizes, etc...)

It's a little over 900 sq ft, so it's a reasonable size.

It could easily reach 40k in repair. houses in that area and similar size and what not sell for 60k.

------------------------------------------------------------------------------------------------------John the cost will depend on what size of apartment building you are talking about 50,75,100,200 units??

I would keep them though cause you're going to have another furnace go up and it's good to have them on hand to loan out.I'm betting its something simple to fix like a thermocouple or an igniter.

I'll bet no other landlord has done that for them before.

So one size filter is all that is needed.

From everything I've read so far my best bet would be to find and buy a duplex and rent half and live in half.