I actually hold my masternodes on Vultr. While i am extremely happy with their service, they are great if you have a single masternode, and they become borderline even with 2-3 nodes.
Moocowmoo is right. You need about 400MB of ram per node. I believe Vultr only has 768MB or ram for the basic. The nodes will start out with about 300MB of ram and creep up over a few days causing your crashing.
You have a few options:
Pay for a hosting providing by Moocowmoo, Splawik, node40, etc. They setup automatic scripts and know how to keep nodes running. Some also have easy ways to vote too.
Get a VPS with more ram. Typically, a 2GB ram VPS can come with a few IPs and is your best bet for cost.
http://lowendbox.com is a good place to find offers and deals. But this is probably not your most reliable option. If a host says they don't offer 24/7 support - that means the end of a billing period they can shut you down at midnight and you wait until they wake up at 9am the next day to help get you started. Or the drive fills up on Saturday, nodes crash, and you wait until Monday for them to fix it. Ideally, you want a service that guaranties 1hr or less downtime 24/7 - not saying they exist in your price range. You can loose several days of payments for just a 90 minute outage.
You can get static IPs from your ISP. Typically, this is more expensive, but in the future with higher ram/disk requirements this might be the better deal. Then run a computer with ubuntu behind a router on a ups.
Hop on this site and look at the masternode service providers for the full list and help on setting everything up.
http://dashmasternode.orgMoocowmoo has a restart script and an easy updater called dashman. See the bolehvpn link he provided in his post to setup both.
Also there is a site dedicated to monitoring your nodes and voting. Install the dwupdater and it will restart and notify you when your nodes have a problem.
http://dashwhale.orgFor status, you can setup a bookmark specific to your nodes with the dashninja by adding your IPs or addresses in the middle - no spaces.
https://dashninja.pl/?mnregexp=%28 put IPs or public dress here separated by | %29#mnlistdetail
If you have any other questions or just want to chat with some of the community, join the Dash Chat Slack - link in my signature below.