Check the house for all needed repairs. Examine the roof, guttering, electrical wiring and plumbing. Go over the crawlspace, attic, porch areas and sidewalks. Hire an inspector to help, if needed, and use a list of planned upgrades when applying for a building permit. Define the budget you will use for repairs and maintenance, leaving the rest of the budget for visual improvements only.
Add insulation in the attic space and exterior walls. Remove drywall or plaster, if needed, to add roll insulation. Check into blown insulation, if you wish to keep plaster walls intact. Go room by room to get drywall or plaster ready for painting. Fix any holes made during the process of adding blown insulation.
Paint all ceilings and walls with light colors. Cover wood flooring and stained-wood baseboards with tarp cloths to protect them from paint drips. Freshen the old wood stain on baseboards or flooring very carefully. Clean the wood with a furniture freshening kit recommended by an antique dealer. Don't disturb the integrity of the baseboards or flooring to redo them unless they are severely damaged.
Redo kitchen cabinets completely, if they are in bad repair. Add new cabinets, but keep a few original cabinets, if they can be used without hurting the look of the kitchen. Don't keep, for example, upper wall cabinets that are dented and scuffed. Do keep an interesting old base cabinet after refinishing it completely. Place this base cabinet on a single wall by itself with open shelving above it.
Add new appliances, bath fixtures and, if needed, flooring throughout the house. Install a new gas range in stainless, new refrigerator and new white bathroom fixtures. Use tile flooring in the kitchen and bathrooms in a light neutral color. Install carpeting or area rugs over bedroom floors or living room areas.