Rabbitry Refurbishment

So my interest in the rabbits seems to have increased. However, due to an extended period of time where my interest waned, I'm now considering a refurbishment of the rabbitry to make it easier to take care of my small charges. Or, more accurately, I'm looking at a nearly complete conversion from a current nearly indoor rabbitry to an external one. Some of my major concerns with leaving them where they are currently are as follows:

1. the barn is very old, poorly designed, and poorly ventilated
2. there is a current fly/rodent problem that regardless of repeated treatments, refuses to go away entirely
3. The barn tend to stay cold in the winter and hot in the summer, regarless of external temperatures
4. there are trees next to the barn on the verge of coming down, if they do it will likely cause a lot of expensive damage to the building, money that I currently do not possess to repair it
5. the barn is currently about 100 yards from the house, not fun having to traverse that distance in inclement weather (snow, ice, rain, wind)
6. The design of the rabbit holes in the barn was originally very piecemeal, and intended to maximize the tiny space, as such the catch trays are large and awkward, especially to clean
7. the barn ceiling is low, with the beams even lower (about 6 ft), the door to the barn has a lip/step and everyone (including me) must duck to enter or risk unconsciousness, I cannot roll any kind of cart into the barn to ease the cleaning of the large trays

Currently there are just 5 rabbits housed inside the barn, there are approximately 50 holes available therein. That is a huge amount of wasted space. I already have 14 cages that need minor alterations to make them ideally suited for a move to the house. It would cost less than $100 to have them ready for new occupants. However, the following are my concerns with trying to complete the move now:

1. the weather, we are at the start of the coldest and wettest part of the year
2. No method for keeping the weather off the cages, I would have to build some kind of roofing system and invest in tarps to cover the front of the cages
3. the new cages are all somewhat small and would not be capable of housing any larger sized animals or does/litters, I would have to return to table breeding method also due to this
4. money is tight, not sure if I could spare even the little bit needed to get the wire to finish those cages

However:
1. closer to the house, I could keep a better eye on everyone
2. does could kindle inside the basement
3. reduced odor/pest problem
4. reduced impact on my allergies