Chad,

I currently own four amateur repeaters with two on 440 and two on 220.

In my experience some of the difficulties are the same as for the sighted 
hams.  Knowledge, money, resources such as climbers and sites, money and the 
willingness to keep learning.

GE Mastr II is one of the more common boxes found to be in service today. 
However, Micor's, EF Johnson, Uniden and many other including Icom, Kenwood 
and Yaesu are all in service too.  The mastr II boxes are getting a little 
long in the tooth.  I recently upgraded my UHF machines to Kenwood 
tkr850-tkr851's.  Computer programmable.  Set up is not totally accessible 
yet but that might be a function of not spending enough time with it.

I recently purchased a Tait 220mhz machine and have an older (70's) vintage 
Micor 220 in service too.  Controllers are easier for us to manage 
especially as you learn the physical lay out of the boards.  Programming 
obviously is easy enough.

Tuning duplexers is something you either need to have someone that knows how 
to do it or hire it out.  Talking SWR meters, help along with volt meters.

The bottom line here is you can do it if you want to and can get the 
funding, assistance and so forth together.  One of my machines is at 2,800 
feet on a 160ft tower.  No, I do not climb.  Actually, two of my machines 
are on this tower with the next two going on a 4000 foot mountain top which 
is less accessible.  Here is where money comes into it in your planning, 
ability to keep the equipment on the air and functioning without many long 
trips to the sites.  Anyway, I know many other blind hams with vastly more 
experience and knowledge on this topic than I and maybe they will chime in 
here.

73 de Brian