Becky first off welcome to House Repair Talk, my experience with T-111 is that it's just a little better than cardboard. When it absorbs moisture it will swell and disintegrate. Residing can be a pricey option down the road and cost will depend on the material you choose to install. Vinyl siding is your cheaper choice(plastic type material, low maintenance). Or you could go with Hardy Board or natural wood siding (both of which will require painting). These are all something you can do later and when your budget will allow. If you go this route, when the existing siding materials are removed make sure new house wrap is installed and all gaps are caulked or sealed.
Good luck with your house search, let us know what you decide.