My husband gets like that and what he found helpful is to limit his "To Do" list to just 10 items per day. (Mine is closer to 25 a lot of days). I find if I write down what I want to accomplish in the day, even tho things may take longer or not get done that day, it really helps keep me focused and I get a lot more accomplished.
The people we got our house from didn't de-clutter and it really harmed their efforts at selling the house - it took them 2.5 years before we came along, and I have to say, we bought this place because we fell in love with the property, the house looked pretty bad at the time.
When we sold our house, we got one of the best realtors in the region and she gave me a 5 page long list of what to do to get the house to
sell quickly. I did almost all of it, and we got two offers at the open house - we accepted one that later backed out (girl was engaged and hadn't consulted her fiancée before making an offer on the house!) and got another offer a week after we put it back on the market. She had us not only declutter (she said because the basement was spacious it would be fine to pack the "clutter" and stack the boxes in the basement, otherwise she'd have had us rent storage until we found a buyer), but also get some "show" furniture that was more modern looking, new drapes, new carpet, fresh paint everywhere, new appliances, new countertops, and more. It wound up costing us around $20,000 but it raised the list price of the house by $50,000 and we got bids that were asking price - no negotiating. The furniture we got was cheap from Wal-Mart, but it served the purpose of looking better than what we had - I got a metal/wood table/chair set with matching barstools for around $200 total, our chairs were dinged and stained with chips, etc. I got some nice looking wood
coffee tables from the Habitat for Humanity Re-Store to replace what we had, sheers from Sears (they have good sale prices!) to replace our faded thermal drapes, etc. We had to get a new bedding set too. It was horrible - cheap polyester but the realtor recommended throw pillows on the bed and this set came with color-coordinated ones that were cheaper than buying them individually. That got donated to charity as soon as we moved, LOL!
We had Home Depot put in the carpet for us, one of their inexpensive "stock" carpets, and it was surprisingly affordable. We also had to repair everything that was in need, and we hired a handyman to knock all those little things out for us - it's great because a lot of them were things we hadn't done because we were "stuck" on how to do one little part of it, but the handyman, with more
experience, knew just what to do and did it right. We had an electrician put in some new modern light fixtures (again, inexpensive from Home Depot, but not tarnished or dated looking like what we had were), both outdoors at the entryways, and in the kitchen and bathrooms. Our master bathroom was in really bad shape so we had the plumber, who also did tile work, tile the floor and
shower enclosure, and to save money we put in a nice
shower curtain instead of replacing the nasty acrylic door.
I also replaced the sagging particle board shelves in the master bedroom closet with a painted entertainment center (for shelving) and some other new shelves, all painted the same gloss brown to look like dark wood. If you buy plywood at Home Depot or Lowe's, they'll cut it for you to whatever dimensions you need so making "custom" shelves becomes pretty easy. And you can get entertainment centers (you know, those tall cabinets they used to put TV's, etc. in) for almost free now that everyone wants flat screen TV's.