First, I was thrilled 11 years ago to find not only a real house with a real barn and existing fencing around MORE than 2 acres--we have 5 acres--for a great price so I could have my horses in the back yard. My horses have 24/7 turnout from April to November, then I stall as needed from November to April.
My (maybe) 80 yo barn has a loft that can hold 500 bales, with stairs, instead of a fireman's ladder, and one of the property's owners built a 16 x 19 ft shelter on the west side of it--VERY useful.
I like that the flooring is concrete bc you can clean it. I kept several horses until they died of old age. There is NO WAY that you can thoroughly clean "rot" from a dirt floor in your barn unless you dig it out and replace it. I'd like to know if the folks with dirt floors are replacing the dirt periodically? MY IMPROVEMENTS are the stalls I've created and a shelter manger.
DH and I in the process of rebuilding the 2 1/2' wide cattle manger on the north side of the shelter so that I can, once again, fill it from the catwalk attached to the west-facing sliding door to the loft.
I padded my cement floors with rubber mats. I prefer 1/2" button cattle mats in the aisles and 3/4" mats in the stalls. Mine have really lasted a long time. Some people do not think that rubber mat padding is adequate. I suggest laying a couple of inches of dirt on top of the cement and then laying down the mats for extra cushioning.
My barn had a 3/4 "stall" of sorts, 8 x 12, and I just hung a 13' pipe gate to close it in. Across the aisle I assembled 3 round pen pieces and a round pen gate and created a 12 x 12 stall in the opposite corner. Next to that (same side) I had a ready made 12 x 16 "stall" where I originally kept my 19yo TWH. There is a skinny door that I used to enter/exit and feed, and he wasn't interested in breaking the folding barn door down, so, though makeshift, it made a dandy stall once I floored it mats, too.
Something to think about, though it may raise the cost. My barn had a fenced in area in front of it. I cannot tell you how many times it contained my Arabian, "Corporal" (1982-2009, RIP), who was my escape artist!.
Here's my place:
Almost forgot--solar lights are awesome. The little ones run on a solar AA or AAA battery and most batteries last about a year. I have them under the fencing by ALL of my gates. On the moonless nights you can see where you're going. If you buy the Christmas ones on clearance, you'll spend about $1/light. If you add about $5/4 replacement batteries, you can see how it cuts your electric bill. The newer ones are on in the morning in the summer, when out nights go from about 9PM-5AM, btw.