The Vox DA5 is a great amp that has more than one input. I commonly use mine (I have three, now) with a guitar or uke and a microphone.
When you added the BASS to the equation, it leaves two amps to mind. Both are Carvin. I own and use about 4 dozen guitar, bass, keyboard amps and P.A. systems. They are all for different applications. I will offer the following suggestions and also ask, what is your application for the amp, KB?
First: The Carvin S400D. It is a 100 watt battery/AC powered self-contained P.A. system. I bought the S400D, the extra battery, the extension speaker with 50' cable, 2 speaker stands and the 12 volt car cord for under a grand. With the extra battery, it will run at full power for over 6 hours on battery. I've used it at several kanikapilas and also an outdoor gig, since I bought it a little over a month ago. Very clean sounding and versatile.
https://www.carvinguitars.com/products/single.php?product=S400D
http://www.carvinguitars.com/manuals/s400d.pdf
In the owners manual (and in my personal experience),
"CHANNEL 1 INSTRUMENT JACK
The INST. 1 jack is designed for instruments such as an acoustic or electric guitar.
CHANNELS 2-4 INSTRUMENT JACK
The INST. jacks 2-4 are designed for instruments or line level inputs such as a drum machine, tape deck, bass guitar, keyboard, an unbalanced mic, etc.. The sensitivity of these jacks are lower than CH 1 so LEVELS 2-4 will have to be turned higher in some cases."
Second: The Carvin AG100D. Captain Mike, at the Ukulele Society has one of these and uses his for slack key guitar. This one is AC only and has two digital effects processors. A 12" woofer gives punchy bass. There is phantom power on the mike input, so you can use a condensor microphone (in addition to any other dynamic microphone). It is under $500 bucks USD.
https://www.carvinguitars.com/products/single.php?product=AG100D
http://www.carvinguitars.com/manuals/AG100D2003.pdf
"The AG100D 100 watt combo amp delivers full, pristine sound through a tuned-port full range speaker enclosure. The 3 input channels are individually designed, one for acoustic guitar, one for bass or a second guitar, and one for mic/PA/keyboard. The mid sweep on CH1 lets you dial in the sweet spot for your instrument. The effects send on each channel accesses either of the TWO lush internal 24-bit effects processors."
Channel one is specially designed for acoustic and electric guitars using a 1/4” phone shielded cable.
Channel two is an instrument/line input. Any unbalanced device such as another guitar, tape recorders, drum machine, or keyboard can be plugged in using a 1/4” phone plug shielded cable.
Channel three is a microphone & line input. Plug a microphone or line level device into the balanced XLR MIC input using an XLR shielded microphone cable and a 1/4” shielded cable from your tape machine. Both can be used at the same time.