Bastion: Sage University

You are awarded a Bastion when you reach 5th level. During downtime, you can invest gold into your Bastion to upgrade it with new facilities and services. At the end of a downtime, you can choose a number of available services equal to your proficiency bonus and gain their effects until the end of your next adventure. You can gain multiple uses of the same service unless otherwise stated. See the original post here.

Sage Bastion: University

The university is a place of arcane secrets and research where the mysteries of the universe are unraveled and the barrier between planes of existence is thin. As a sage, you can use your University to obtain vital knowledge and enhance your arcane abilities.

Study (Tier 1). When you invest 500 gp in the university, it gains a small room with a desk, bookshelves, scribing materials, and a research assistant. The study offers the following services:

• General Research. Choose one of the following: Arcana, History, Nature, or Religion. You gain advantage on Intelligence checks based on that particular skill until the end of your next downtime.
• Specialized Study. You research an important truth that lets you succeed on 1 Intelligence check of your choice during the next adventure. This increases to 2 checks at Tier 2 and 3 checks at Tier 3.
• Scribe Spell Scroll. You spend the money to craft and gain a spell scroll of 3rd level or lower. Alternatively, you can spend the money to craft two spell scrolls, and your assistant will complete them at the end of your next adventure. The spell level maximum increases to 5th level at Tier 2 and 7th level at Tier 3.

Studio. When you invest 1,500 gp in the university, it gains an arcane studio with spell components, scales, and an apprentice hireling who knows basic spells. The studio offers the following services, which last until your next downtime:

• Practice Cantrip. Choose one cantrip from the Wizard spell list. You know that cantrip until the end of your next downtime.
• Distill Energy. Choose one of your spells of 3rd level or lower. You can maximize the dice of that spell instead of rolling. You can do this twice at Tier 2 and three times at Tier 3.
• Mind Exercises. Once when you fail a check to maintain concentration, you can choose to succeed instead. You can do this twice at Tier 2 and three times at Tier 3.

Arcane Forge. When you invest 7,500 gp in the university, it gains a workshop equipped with arcane implements, as well as an arcanist skilled at enhancing magic items. The arcane forge offers the following services, which last until your next downtime:

• Enchant Weapon. Choose a weapon. It gains a magical +1 bonus to attack and damage rolls. This bonus increases to +2 when the university reaches Tier 3.
• Protect Armor. Choose a suit of armor. The creature wearing it gains resistance to a damage type of your choice (except for bludgeoning, piercing, or slashing).
• Overcharge. Choose a magic item that has charges. The item gains 1 more charge, and instead of rolling to determine how many charges it regains, the die is maximized.

Dissertation (Tier 2). When you invest 15,000 gp into the university, you complete a long essay or book that sets you apart in your field of knowledge expertise. When you complete this investment, you gain the following permanent benefits:

• Accolade. Your Intelligence or Wisdom score increases by 1, to a maximum of 21.
• Ingenuity. When you or an ally within 30 feet of you fails a saving throw or an ability check, you can use your reaction to add your Intelligence modifier to the result. If that causes it to succeed, you cannot use this feature again until you take a short or long rest.
• Professorship. Your lifestyle increases by one step at no additional cost.

Alchemy Lab. When you invest 25,000 gp into the university, it gains an alchemical laboratory complete with a cauldron, flasks, burners, alembics, and other supplies. A skilled alchemist hireling manages the laboratory, and a crew of herbalists keep the lab stocked with ingredients. The alchemy lab offers the following services:

• Brew Potion. You gain one free potion of Rare rarity or lower. Alternatively, you spend the money to brew and gain one potion of Very Rare rarity or lower; or you can spend the money to brew 3 potions that will be finished at the start of your next downtime. The rarity thresholds change to Very Rare and Legendary, respectively, at Tier 3. 
• Transmute. You transmute mundane stones and litter in the university into pure gold worth 3d6 x 100 gp.
• Mithridate. You gain resistance to poison damage and advantage on Constitution saving throws to prevent the poisoned condition.

Dorms. When you invest 60,000 gp into the university, it gains a wing with student housing, a mess hall, and supplies for 10 associate professors (apprentice wizards) and 3 deans (mages) under your command. These teachers instruct your students, and the deans defend your university with magic, but if any die, new ones can be recruited for 200 gp each. The dorms offer the following services:

• Recruit Apprentice. You gain the services of a student during your next adventure. They act as a Mage Spellcaster sidekick of your level under your command and have a Friendly disposition to you as long as you treat them fairly. The student is equipped with an arcane focus.
• Symposium (costs 2 services). Make an Arcana, History, or Nature check using your Intelligence score. You gain gp equal to the result x 100.

Scholastic Deanship (Tier 3). When you invest 100,000 gp into the university, you establish a deanship. Your university and your status as archchancellor of it becomes known throughout the land. When you complete this investment, you gain the following permanent benefits:

• Archchancellor. Your Intelligence or Wisdom score increases by 2, to a maximum of 23.
• Scholarly Feat. You gain a feat of your choice. Your Humanoid followers in the university gain this feat, and when you use the Recruit service from your Garrison, the sidekick gains this feat also.
• Aristocracy. Your lifestyle increases by one step at no additional cost.

Orrery. When you invest 250,000 gp into the university, it gains a large magical laboratory and observatory, complete with targets, a permanent circle of teleportation, spell components, and a scrying focus. It also gains the services of an archmage to maintain it. The orrery offers the following services:

• Spell Components. The orrery has a scrying pool or mirror usable as a component for the scrying spell, as well as a permanent circle of teleportation.
• Scry. You cast the scrying spell (DC 20) once during your downtime without expending a spell slot.
• Modify Spell. Choose one spell that you know. You can make one of the following changes to it, which lasts until the end of your next adventure:
• You change the damage type.
• You change the saving throw type.
• You increase the spell's casting range by 50%.
• You remove either the spell's verbal or somatic component requirement.

Planar Gate. When you invest 500,000 gp into the university, you completes construction of a planar gateway acting as a hub between the planes of existence. You also gain planar charts, a collection of arcane tomes, and the services of a seasoned archmage and 4 elemental myrmidons (one of each element). The planar gate offers the following services:

• Planar Guardian. You summon an Aberration, Construct, Elemental, or Fiend of CR 10 or lower that joins you for your next adventure. The guardian is under your control and will protect you with its life, but it cannot regain hit points. It returns to its home plane when it reaches 0 hit points.
• Stable Warp Link. You gain 1 use of the plane shift, demiplane, or teleport spell until the end of your next adventure. When casting teleport in this way, the d100 roll is treated as rolling 100. The demiplane accessed by this service is always the same one.
• Arcane Enhancement. For the duration of your next adventure, when you cast a spell of 3rd level or lower, roll a d3. If you roll equal to or higher than the spell's level, the spell slot is not expended.