Renovation Mode is only available to Sims in the Architectural Designer career. It is similar to the build mode and buy mode in the Sims 3. While in this mode you can see a list of requirements for the current renovation, if the requirements are not met, the job will count as failed. The player has a budget given at the beginning of the job, although they can overspend on their budget.
While in build/buy mode there is a home inventory box that contains items from your active sims home inventory, this is where you will find your sims creations (paintings, sculptures, inventions). There is a small glitch with your home inventory box in renovation mode. If you grab an object from your home inventory box and drop it back in the inventory without placing it, or if you do place the object and then "undo" the placement your client will receive credit for the full price of that object added to their budget and your sim will be deducted that amount from his/her own household funds.
To activate this mode, players must first get work opportunities based on the story progression feature, for example if a pair of Sims in the neighborhood have had a baby they may request a nursery, or a sim with the Bookworm trait may request a reading room. Each job is given a budget, and it will be changed depending on what you buy and sell (it is possible to sell items you did not buy). Client sims will review the work, and based on how good it is, will pay the architect money, with a chance of a bonus.