> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vast.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Choosing Instances Overview

> Learn the complete process of selecting and renting a GPU instance on Vast.ai, from choosing templates to configuring and launching.

Renting an instance on Vast.ai involves three main steps that work together to get you the exact computing environment you need.

## The Rental Process

<Steps>
  <Step title="Choose Your Template">
    Select or customize a Docker template that defines your software environment - PyTorch, TensorFlow, Stable Diffusion, or custom configurations.
  </Step>

  <Step title="Find Your GPU">
    Search and filter through available offers to find GPUs that match your performance needs and budget.
  </Step>

  <Step title="Configure & Rent">
    Set your disk size, review the offer details, and launch your instance.
  </Step>
</Steps>

## What You'll Need to Decide

Before renting an instance, you'll make key decisions about:

* **Software Environment**: Which Docker image and launch mode (SSH, Jupyter, etc.)
* **Hardware Requirements**: GPU type, VRAM, CPU, and system RAM needed
* **Storage Size**: How much disk space (cannot be changed after creation)
* **Instance Type**: On-demand for reliability or interruptible for cost savings
* **Budget**: Maximum price you're willing to pay per hour

## Quick Start Path

For the fastest path to a running instance:

1. **Use a Recommended Template** - Pre-configured and tested
2. **Sort by Price** - Find the best deals quickly
3. **Check Reliability Score** - 95%+ for important work
4. **Start with On-demand** - Upgrade to reserved later if needed

## What's in This Section

<CardGroup cols={2}>
  <Card title="Instance Types" href="/guides/instances/choosing/instance-types" icon="layer-group">
    Understand on-demand vs interruptible vs reserved options
  </Card>

  <Card title="Choosing a Template" href="/guides/instances/choosing/templates" icon="cube">
    Understanding and selecting templates for your needs
  </Card>

  <Card title="Finding & Renting" href="/guides/instances/choosing/find-and-rent" icon="search">
    Search, filter, configure, and rent GPU instances
  </Card>

  <Card title="Reserved Instances" href="/guides/instances/choosing/reserved-instances" icon="badge-dollar">
    Save up to 50% with prepayment options
  </Card>
</CardGroup>

## Common Questions

### How long does it take to start an instance?

Usually under 5 minutes with recommended templates. Large custom images may take longer on first launch.

### Can I change my configuration later?

* **Template**: No, you need a new instance
* **Disk size**: No, fixed at creation
* **Instance type**: Can convert on-demand to reserved only

### What if the GPU I want isn't available?

Set up search alerts or try different regions. Availability changes frequently as a marketplace.

## Next Steps

Ready to get started? Begin with **[Instance Types →](/guides/instances/choosing/instance-types)** to understand your options.